I haven't seen Argo yet, so I can't say much about it winning Best Picture. I'll watch it as soon as I can.
I'm a bit disappointed with Daniel Day-Lewis winning Best Actor. Fat chance he was going to win, but in my opinion Joaquin Phoenix gave a way better performance in The Master.
I haven't seen Silver Linings Playbook yet either (I think it's going to be out in theatres here soon) so I can't say much about Jennifer Lawrence winning Best Actress. I can hardly imagine she really outperformed Emmanuelle Riva though, but I'll see.
Christopher Waltz and Anna Hathaway winning best supporting actor and actress is cool with me. Didn't expect Christopher Waltz to win, but I'm happy to see that he did.
I feel like Wreck-It-Ralph should've won Best Animated Picture. Brave was pretty good too in my opinion, but it looked more like a run-of-the-mill Disney film (by Pixar).