Guardians of the Galaxy is the best Marvel movie since the original Iron Man, in my eyes.  Great characters, light-hearted fun, and awesome ties to the Marvel Cinematic Universe.  Exodus nailed it for me--this felt like the best Star Wars movie since ROTJ.
Pratt, Cooper, and especially Batista were great.  Saldana was by-the-book, but obviously dayum-looking.  This is coming from someone unfamiliar with the comics, but I'm definitely picking up some issues now.  They're dirt cheap right now.
I really hope some aspects and characters of Guardians makes their way into Avengers 2.  Pratt with RDJ would be comedy gold.