In 2003, Ms. Britney Jean Spears was on top of the world. Not only was she the most sought-after pop tartlet in the universe, but she’d just released her fourth album, “In the Zone,” a full-blown, slinky n’ sexy denouncement of the teeny-bop sugar-pop she’d been known for in the past. At this point in her illustrious career, Brit was an unstoppable force. Everything was coming up roses for the Louisiana sweetheart.

But in the wise words of George Harrison, “All things must pass.” Flash-forward to 2007 and things have certainly taken a dramatic turn for the worse.

Take into account the quickie Vegas wedding that lasted all of 48 hours, the white-trash weddin’ to Kevin Federline, the divorce, the rehab stint, the coochie-flashing, the head shaving, the custody battles – well, it’s certainly been a tough few years for Britney. The hot body’s a thing of the past, the fan appreciation’s swirling rapidly down the drain, and the never-ending applause is just a ghostly echo in the halls of her Malibu mansion.

So who would’ve thought that while Britney was committing petty crimes, causing paparazzi riots, and raising Starbucks’ stock with every passing day, she was also in the recording studio creating an absolutely fabulous album of slick, near-perfect club-hopping pop music?

With the release of her fifth studio album, “Blackout,” Brit’s out to show that she’s not going anywhere; she’s just been taking a little breather. It’s the nicest kind of surprise a Spears fan could imagine, so get ready to don your dancin’ shoes.

The album’s first single, “Gimme More” has been continuously thrumming through speakers everywhere, packing dance floors across the nation. Don’t be ashamed to admit it’s good; “Gimme More” is classic crazy-sexy-cool Britney at her grinding and gyrating best.

“Radar” is the catchy pop diamond that Barbados sensation Rihanna wishes she’d released; it gives her omnipresent summer single “Umbrella” a run for its money with shimmering, pulsating beats. (Sure, the lyrics leave much to be desired, but so does “In the dark/you can see shiny cars.” What, Rihanna?)

But it’s “Piece of Me” that is Britney’s triumph; it’s her public declaration of everything that’s happened to her in the last few years: “I’m Miss Bad Media Karma/ another day, another drama/ guess I can’t see the harm in workin’ and bein’ a mama,” she addresses her public in a herky-jerky drawl. “I’m Mrs. Lifestyles of the Rich and Famous/I’m Mrs. Oh my God that Britney’s shameless.” She complains about the paparazzi’s constant surveillance of all things Spears, but does it in a way that intrigues instead of annoys. (Lindsay Lohan’s “Rumors”, anyone?) “Heaven on Earth” is a deliciously fizzy slice of 80s synth-pop goodness; this is Britney back to her sweet, candy-coated roots and it is delectable.

Certain tracks sound a bit like Britney’s been hanging with Swedish indie-dance duo The Knife, or perhaps taking a cue or two from French floor-packers Justice. “Freakshow” and “Toy Soldier” are sure to be as popular on the dance floor as “Toxic” and “Slave 4 U” proved to be.

However, she falters a bit with “Get Naked (I Got a Plan)” which veers toward the blasé despite its attempts to tease and titillate. “Hot as Ice,” where Britney decides it’s a good idea to sing in her higher register is another sub-par venture; she sounds like a nasally 8-year-old.

For the most part, “Blackout” is a no-holds-barred nonstop dance party, though the final track happens to be a ballad titled “Why Should I Be Sad,” better deemed “The Ballad of Britney & Kevin.” This sure seems to be Britney’s confessional take on their marriage and divorce: “I sent you to Vegas with a pocket full of papers/ and put no ultimatums on you/ I thought nothing could separate us/ but it seemed like Vegas just brought out the player in you.” So perhaps that’s what went wrong with Spederline? Anyway, “Why Should I Be Sad” is at times trite as Britney’s ballads are wont to be, but certainly the album benefits from its inclusion; it’s the morning-after converse to the martini-swilling, table-dancing fun of songs like “Perfect Lover” and “Ooh Ooh Baby.”

Britney obviously hasn’t matured as an artist – she’s still cooing breathlessly, her voice often manipulated by a studio magician’s sleight-of-hand. Her vocal power certainly hasn’t strengthened over the past few years, but she blossoms with strong producers and even stronger songs, both of which she has in multitudes on “Blackout.” (Pharrell and Danja take turns helming the S.S. Spears this time around; there’s no hyper-pop Max Martin in sight.) But Britney knows what works for her, and she works it.

“I know it’s been awhile but I’m glad you came,” she welcomes her listener to open “Break the Ice.” So are we, Britney, so are we.