Britney Spears this week becomes the first female solo artist in the history of Billboard's pop album chart to amass six #1 albums

Britney Spears this week becomes the first female solo artist in the history of Billboard's pop album chart to amass six #1 albums before her 30th birthday. Spears, 29, achieves the feat with her new album, Femme Fatale, which enters the chart at #1. Until this week, Mariah Carey was the youngest female solo artist to gather six #1 albums. She was 38 when she picked up her sixth #1 album, E=MC2, in 2008.

Only two male solo artists have notched six #1 albums before turning 30. Elvis Presley nabbed his sixth #1 album (1961's Something For Everybody) when he was just 26. Elton John landed his sixth (1975's Captain Fantastic And The Brown Dirt Cowboy) when he was 28.

Only four other female solo artists have amassed six or more #1 albums (no matter their age). Barbra Streisand leads the pack with nine, followed by Madonna with seven and Mariah Carey and Janet Jackson with six each.

Femme Fatale sold 276,000 copies in its first week, which is the second biggest one-week total so far in 2011. Only Adele's 21 sold more copies in one week (352,000). That said, this is the thinnest first-week total for a Spears studio album since her debut album, ....Baby One More Time, sold 121K in its first week in January 1999.

Femme Fatale (great title) sold far fewer copies in its first week than Spears' last album, Circus, which sold 505K copies in December 2008. But it sold nearly as many digital copies (113K for this album, compared to 118K for Circus), which means digital sales accounted for a much higher percentage this time out.

Five songs from Femme Fatale are listed on Hot Digital Songs, but "Hold It Against Me" isn't among them. How can that be? (The smash, which reached #1 on both the Hot 100 and Hot Digital Songs, was #66 on the digital chart last week.) It's the impact of returns due to customers' "Complete My Album" option. Enough fans took advantage of that clever gimmick that the song showed negative sales this week. (Whoever came up with that idea deserves a raise.)

Wiz Khalifa's Rolling Papers debuts at #2, with first-week sales of 197,000. This is the first time that two albums have debuted with sales north of 190K in the same week since Kanye West and Nicki Minaj scored in November. Wiz Khalifa's song "Black And Yellow" tops the 3 million mark in digital sales this week, but that was no guarantee that the album would sell well. There are dozens of examples of artists with giant singles whose albums sold modestly. You really just never know.

Adele's 21 holds at #3 in the U.S. (and may well return to #1 next week). It also holds at #1 in the U.K. for the 10th straight week. It's the first album by a female solo artist to spend 10 consecutive weeks at #1 since the U.K. album chart was introduced in 1956. The old record was held by Madonna's The Immaculate Collection, which held the top spot for nine straight weeks in 1990.

The Official Charts Co., which monitors U.K. sales, notes that 21 sold 250,000 copies in the U.K. this week. That's its biggest weekly total to date, which suggests that the album hasn't run its course at #1. If it spends one more week on top, it will tie Alanis Morissette's Jagged Little Pill and Shania Twain's Come On Over for the longest run at #1 (continuous or not) by a female solo artist. Check back next week and see if Adele does it.

Chris Brown's F.A.M.E. drops from #1 to #4, but here's a stat that may surprise you. The album has sold more copies in its first two weeks (362,000) than Brown's last album, Graffiti, has in its entire run (342,000). Graffiti was released just 10 months after Brown's assault of then-girlfriend Rihanna. Memories fade. Fans forgive.

Radiohead's The King Of Limbs debuts at #6, with sales of 69K copies. The tally consists of 46K CDs and 23K digital copies. The album's previous digital sales, through the band's website, aren't counted in the album's "release-to-date" total.

Snoop Dogg's Doggumentary debuts at #8. It's Snoop's first album since he landed his biggest pop hit, Katy Perry's "California Gurls," which topped the Hot 100 for six weeks last year. This isn't the first Mr. Dogg has played with his stage name in an album title, witness Doggy Style, Tha Doggfather and No Limit Top Dogg.

Two contemporary gospel albums appear in this week's top 10 (perhaps to help us atone for all the "F word" hits). Kirk Franklin's Hello Fear drops from #5 to #9 in its second week. Mary Mary's Something Big bows at #10. It's the third top 10 album for both acts.

Adele and Justin Bieber this week become the first artists to sell 1 million or more albums in the U.S. in 2011 (combining all their releases). Adele has sold 1,070,000 albums since the first of the year. Bieber has sold 1,053,000. These artists don't otherwise have much in common, but that's pop music for you.

My headline for Chart Watch: Songs will be "And Then There Were Four." It has something to do with "E.T." by Katy Perry featuring Kanye West, which tops Hot Digital Songs for the fourth straight week and will probably lead the Hot 100 for the second week. But what does it mean? Check back later today and find out.

Here's the low-down on this week's top 10 albums.

1. Britney Spears, Femme Fatale, 276,000. This new entry is Spears' sixth #1 album; her eighth to make the top 10. Five songs from the album are listed on Hot Digital Songs, topped by "Till The World Ends," which jumps from #18 to #15.

2. Wiz Khalifa, Rolling Papers, 197,000. This new entry is the rapper's third album, but his first for a major label. Seven songs from the album are listed on Hot Digital Songs, topped by "No Sleep," which slips from #2 to #6.

3. Adele, 21, 94,000. The former #1 album holds at #3 in its sixth week on the chart. It has been in the top five the entire time. Three songs from the album are listed on Hot Digital Songs, topped by "Rolling In The Deep," which jumps from #11 to #9.

4. Chris Brown, F.A.M.E., 91,000. The former #1 album drops from #1 to #4 in its second week. Five songs from the album are listed on Hot Digital Songs, topped by "Look At Me Now" (featuring Lil Wayne and Busta Rhymes), which jumps from #8 to #5.

5. Various Artists, Songs For Japan, 71,000. The digital-only compilation jumps from #6 to #5 in its second week; its first full week of sales. The arrival of the CD this week will help push it to #2 next week.

6. Radiohead, The King Of Limbs, 69,000. This new entry is the band's fifth top 10 album.

7. Jennifer Hudson, I Remember Me, 56,000. The album drops from #2 to #7 in its second week. "Where You At" drops from #77 to #149 on Hot Digital Songs.

8. Snoop Dogg, Doggumentary, 50,000. This new entry is Snoop's ninth top 10 album. He scored his first, Doggy Style, in November 1993.

9. Kirk Franklin, Hello Fear, 46,000. The album drops from #5 to #9 in its second week.

10. Mary Mary, Something Big, 42,000. This new entry is the sister duo's third top 10 album, following Mary Mary (#8 in 2005) and The Sound (#7 in 2008).

Five albums drop out of the top 10 this week. The Strokes' Angles drops from #4 to #18, Panic! At The Disco's Vices & Virtues dives from #7 to #32, Mumford & Sons' Sigh No More drops from #8 to #11, Bobby V's Fly On The Wall plummets from #9 to #60, and Lupe Fiasco's Lasers drops from #10 to #16.

The Sucker Punch soundtrack jumps from #31 to #22. It's the week's #1 soundtrack.

Jason Aldean's My Kinda Party jumps from #26 to #23. It's #1 on Top Country Albums for the fourth week. It's the first album by a male solo artist to top the country chart that long since Brad Paisley's 5th Gear in the summer of 2007.

The week's top TV soundtrack is Grey's Anatomy: The Music Event, which debuts at #24. The album features the cast performing such songs as Snow Patrol's "Chasing Cars" and The Fray's "How To Save A Life." (The cast's renditions of those songs enter Hot Digital Songs this week, though in each case, the original hit debuts a little higher.) This is the third album from Grey's Anatomy to make the top 30. Two albums of music that was featured on the show made the top 20 in 2006-2007, when Grey's was at its buzzy peak.

Two volumes of E-40's Revenue Retrievin' debut in the top 50. Graveyard Shift bows at #40. Overtime Shift opens at #42. The albums were just 200 units apart in sales, which suggests that most fans bought both.

Elton John's 2007 compilation Rocket Man-Number Ones re-enters the chart at #45 in the wake of American Idol's "Elton John Week." (Elton and Leon Russell also appeared on Saturday Night Live.) Rocket Man sold 13,000 copies this week. American Idol had 24.2 million viewers, which means about one in 2,000 Idol viewers bought the album. (That's the difference between watching TV for free and buying something.)

Elton's album is #1 for the first time on Top Catalog Albums. It's the first album with the magic phrase Number Ones in (or as) its title to top the catalog chart since Michael Jackson's Number Ones led the list for 28 weeks in 2009-2010. George Strait's 50 Number One Hits topped the catalog chart in May 2009. The Beatles' 1 and Elvis' Elv!s: 30 #1 Hits also topped the catalog chart.

Four Elton songs re-enter Hot Digital Songs this week. Details in Chart Watch: Songs.

A 25th anniversary concert rendition of Les Miserables is #1 on Top Music Videos. The concert features such notables as Nick Jonas (of Jonas Brothers) and Lea Salonga (the voice of Disney's Mulan and Princess Jasmine). A "10th Anniversary Concert" of the hit musical topped the Music Video chart for 22 weeks from October 1996 to March 1997.

Hop was #1 at the box-office over the weekend.

Coming Attractions: Hollywood Undead's American Tragedy is expected to be next week's top new entry, with first-week sales in the 60K range. Also due: Asking Alexandra's Reckless & Relentless, Robbie Robertson's How To Become Clairvoyant, Daft Punk's Tron: Legacy Reconstructed, Jim Jones' Capo, Mint Condition's 7 and a reissue of Rush's 1981 album Moving Pictures.