Jack White's first solo album, Blunderbuss, debuts at #1 this week in both the U.S. and the U.K.  This marks the fourth time that the first solo album by a prominent member of a group or duo has reached #1 in both countries. Blunderbuss follows George Harrison's All Things Must Pass, George Michael's Faith and Beyonce's Dangerously In Love. All three of those artists had had "transatlantic #1" albums with their famous groups (the Beatles, Wham! and Destiny's Child, respectively) prior to their solo debuts. White nearly did too, but the White Stripes' 2007 album Icky Thump, which hit #1 in the U.K., peaked at #2 in the U.S.

Blunderbuss is White's eighth top 10 album on The Billboard 200, following three albums with the White Stripes, two with the Raconteurs and two with the Dead Weather. The White Stripes first cracked the chart in March 2002 with White Blood Cells. The Stripes' last three albums won Grammys as Best Alternative Music Album (which puts the band in a tie with Radiohead for the most wins in the category's 22-year history). White has amassed nine Grammy Awards in all.

Florence + the Machine's MTV Unplugged enters the current Billboard 200 at #51. It's the highest-charting Unplugged album in a little more than five years, since Korn's MTV Unplugged hit #9 in March 2007.

Thirty-two artists have charted with Unplugged albums in the past 21 years. They're a surprisingly diverse bunch. In addition to the pop and rock artists who are most often associated with the series, Latin, R&B, hip-hop, traditional pop and Contemporary Christian artists are also represented. (Two Various Artists albums have also charted.)

Until about four months ago, relatively few pop fans had heard of fun., an indie pop group from New York City. More had heard of R&B singer Janelle Monae, who performed on the Grammys in February 2011, but most probably couldn't have named one of her songs. This week, these newcomers break a record previously held by two of the biggest superstars in pop music, Eminem and Rihanna. "We Are Young" becomes the first song in digital history to top 300K in weekly sales six times. The old record was held by "Love The Way You Lie," which topped 300K in weekly sales five times in the summer of 2010.

And "We Are Young" will probably extend its record. It sold 390K copies this week, its best showing to date. It may well top 300K for one to three more weeks.

Madonna's MDNA tumbles from #1 to #8 in its second week on The Billboard 200. Sales plummeted by 87%, from 359K to just 48K.  That's the largest second-week decline for an album that debuted at #1 since Nielsen SoundScan began tracking sales for Billboard in 1991. It surpasses two albums from last year: Lady Gaga's Born This Way (which dove by 84% in June) and Mac Miller's Blue Slide Park (which dropped off by 83% in November).

Sales of Michael Buble's Christmas plummeted by 96% the week after Christmas, but it was in its 10th week at that point. And the drop was inevitable. Once Christmas is over, it's over. Gaga's first week was inflated by an infamous 99-cent promotion. And Miller isn't exactly an icon and an international superstar.

So what's the story with Madonna?

Madonna's opening-week sales tally included about 185K copies that were bundled with the purchase of tickets to her upcoming tour. It's impossible to know how many of those fans would have bought the album if it hadn't been bundled with the concert ticket. Some would have, to be sure. But others wanted to see the show and didn't much care about the new album. It's the same story with many other veteran artists, from the Rolling Stones to Barry Manilow.