1. The ball is in his/her/their court.
2. I could care less.
3. "Literally" when used to mean "figuratively" (example heard on NPR a few weeks ago: "Israel's prime leader is literally larger than life." Really? How large is life, 5'9"?)
4. fo' shizzle (or really any word to which -izzle is added in a pathetic attempt to be cool)
5. I'm not sexist/racist, but . . .
6. Raise the roof! (actually said by my boss last week, thinking this was a new and totally hip phrase)