by Joanna Fung
Move over, Matthew McConaughey! This new batch of yummy 30-and-younger guys are quietly replacing all the George Clooneys and Brad Pitts of Hollywood. The youngins are dominating the silver screens, runways and even tennis courts. Flip through our celebrity photo gallery to see the hottest 30-under-30 guys. But beware: You might discover the inner cougar in you.

For more celebrity photos, visit the Star Snapshots gallery. Plus: Check out more sexy stars in our Hollywood's Sexiest 40-Somethings slide show.