Mary Elizabeth Winstead and Shia Labeouf.
Two of the nominees for the MTV Best Kiss 2008 are the kiss between Shia Labeouf and Sarah Roemer in "Disturbia":
"Following scene after scene of teasing sexual tension, these two up-and-coming hotties finally cave in and make out".
And the kiss between Ellen Page and Michael Cera in "Juno":
"In one of the snarkiest movies ever, the most memorable moment may be the most sincere one. Effortlessly cool".