Seen the movie twice already. Once in 3D, once without. Loved it both times. I missed the troll doll flying in Quill's ship when its in freefall in 2D, but caught it in 3D.
One obvious joke that I loved, but not many people seemed to catch in my screenings was 'He not talk good like you and me. His vocabulistics is limited to I, Am, and Groot, exclusively in that order'
People laughed at the Groot part, but what makes this line golden for me is Rocket thinks his speech is okay while using phrases like 'not talk good' and 'vocabulistics'. This line made me fall in love with Rocket