Pop Crunch — For someone whose made a career out of poking fun at celebrities, Perez Hilton sure has a lot of famous friends. Christina Aguilera sang Happy Birthday to the popular bloggers during his 31st birthday bash at The Viper Room in West Hollywood on Satur... more info

411 Mania — Check out Christina... more info

The Daily Mail — Roaring into action: Christina Aguilera shows off her curves in leopard-print leotard more info

Perez Hilton — Wow. Wow. Wow. Our 31st bday bash on Saturday night was the best birthday party we have ever had!!!!! The legendary Viper Room on Sunset Blvd. was filled with our closest friends and family and some really good music! Miz Christina Aguilera was our s... more info

Perez Hilton — Channeling her inner Marilyn Monroe, the lovely Miz Christina Aguilera sang Happy Birthday to "Mr. Perezident" at his 31st birthday bash on Saturday night. Check it out above! And, click here to watch part of her performance of Lady Marmalade. more info

ContactMusic — CHRISTINA AGUILERA thrilled blogger PEREZ HILTON by serenading him at his 31st birthday party in Hollywood on Saturday night (28Mar09). The singer recreated Marilyn ... more info

The Mirror — Christina Aguilera finds out the hard way that wearing spots can be a rash decision. more info

Perez Hilton — Miz Christina Aguilera gives le glamour in the new ad for jewelry designer Stephen Webster. Gorge! more info

Pop Crunch — Rihanna has been spotted shopping for real estate in Hollywood Hills. The Grammy-winning singer spent Monday afternoon looking at properties in the same exclusive section of Los Angeles where celebrities like Leonardo DiCaprio, Nicole Richie and Cam... more info

Idolator — One day after word had surfaced that someone was going around saying that the Final Four for this season of American Idol was already a lock—and that said pool would consist of Danny "I Love My Dead Wife And Jesus" Gokey, Adam "Jake Shears" Lambert... more info