It was Britney Spears' birthday yesterday, but her fans are getting the present: a brand-new album from the 32-year-old star.

The disc, Britney Jean, arrives in stores just as the star is ramping up for her Las Vegas residency at the Planet Hollywood Resort Casino.  To mark the occasion, Tuesday afternoon, Britney will make what's being described as an "elaborate arrival" to the venue down the Las Vegas strip.  According to the Las Vegas Sun, spectators will witness "an outrageous and over-the-top mobile-stage spectacular," featuring "a 'Tree of Life'" that will spawn "acrobats and sexy dancers," and Britney herself will appear "through a wall of fire tunnel."

The two-year residency, Britney: Piece of Me, starts December 27 and is described as "the most intimate, yet dynamic, concert experience of her career."

While the show will feature all of Britney's hits, it's not clear if the material on Britney Jean will be included.  Billed as her "most personal album ever," the disc has been streaming on iTunes for the past week, and most critics agree that, while the album isn't actually that personal, it's still pretty good. 

Britney co-wrote every track, and other writers on the songs include David Guetta, Katy Perry, Sia andWill.i.am.  As for guest appearances, there are three: one by Will, who is the album's executive producer, as well as one from T.I. and one from Britney's little sister, Jamie Lynn Spears.  Fans should savor the album, because it's not likely that they'll be getting another one anytime soon.  As she told BBC Radio 1, "I'll take a break after this one for a while."

"This album is different from any album I've ever done," Britney told BBC Radio 1. "It's very moody and electric and different, so it's pretty cool."  As for the title, she told London's Capital FM, "It's my personal name that my family calls me. It's a term of endearment and I just wanted to be able to share that with my fans."

If you don't find Britney Jean the album personal enough, hold out for the upcoming I Am Britney Jeandocumentary, which is coming to E! on December 22nd.  "Been filming for months to capture EVERYTHING we've put into the Vegas show & album. So much to show the world. Can't wait!," Britney wrote on her website.

You can hear more from Britney on Tuesday when she appears on The Ellen DeGeneres Show.