This episode takes place directly after winter break, yet they aired the wedding one first and I don't think it was a good idea: this one's far stronger and it builds up several arcs (the main UST pair, the rift between two best friends, I love the continuity it shows, and it reminded me of the first season with things like Abed re-enacting things, Annie eyeing Jeff's body, references to Seacrest ... I love the fact that, first, Chang was actually *in* the episode, and he hada an interesting subplot that will be revisited in a future episode.
Abed's selfishness is starting to take its toll. I love the character and I love to see he's got flaws. I wonder if that's one of the reasons why things didn't happen between him and Annie (she's only actually been attracted to him when he's been playing a character).