"Blur" is a repetitious, self-pitying electronic ballad about not remembering what happened last night. "If U Seek Amy," a feisty club anthem about drugs and drinking, makes a statement about not caring what people think. For the album's title track, Spears brags about her position in life: "There are only two types of people in the world/the ones that entertain, and the ones that observe/Well baby, I'm a put-on-a-show kinda girl."

Although she has made a career with her over-produced, raspy and nasally vocals, there are a few uncomfortable moments where Spears experiments with a more mature singing style. She attempts to explore new pitch ranges and depth on "My Baby," but it just comes across as awkward and insincere. She does her best sticky-and-sweet Madonna impression on the funky, disco-tinged "Lace and Leather," and sounds more at-home mimicking her Pop Queen idol than trying to expand on her own.

"Broken Glass" is one of the shortest, but most infectious dance-floor tracks. No doubt, this just-under-three-minutes-long tune will get remixed and extended by DJs everywhere. Spears also hits the mark with the down-tempo, love-infused "Unusual You," and the regretful, R&B-minded "Out From Under."

"Circus" has a fair share of filler and lackluster moments, but even the less impressive tunes are adequate to be a party's background-music. At the very least, there are some good no-brainer songs for the morning-after hangover.