It's too early to get rid of Graham IMO. WR is a hard position to get up to speed at in the NFL. His drops were very noticeable in the Seattle game, but who knows what was happening (e.g. did he dislocate a finger that week?).
Unless he has a total melt down, I'd like to see the Bills stick with him at least 3 years. He looked better to start the season than I expected from a rookie. Let's see if he gets even stronger this offseason.
Brad Smith is one of our few playmakers. Unfortunately he seems inconsistent to me. He's a great emergency WR if we have him on the roster for other reasons. While he flashes big plays, I don't think he's a great WR.
I think Nelson is a keeper, a clutch player that is go-to on 3rd down. I'd rather have him in the slot than Stevie, but would like an offense were we move players around to stress/test the defense.
I'm confused on Donald Jones, who seems to run hot and cold. In 2011 I was not very impressed toward the end, but then last year he came in and performed much better than I was expecting. He definitely deserves to compete for a spot. My best guess is that he's good enough when healthy, but not very good at playing through the minor injuries that are going to come up each year.