I'll answer the last question first-he would definitely, IMO, be a good 2nd round pick. He's fairly polished coming out of college and, though he'll definitely need some work (all college WR do, even Rogers) he should be solid.
Can he become a # 1 WR? It's hard to say. He's 6'2 210, which is good size, and he seemed to have more than blazing speed in every game I've watched. Still, the experts are saying he's not fast enough for a #1 guy, that he'll be a possession receiver. Hey, this kid caught 42 balls for over 700 yards in the Big Ten, at PENN STATE, no less. Since we're traditionally not a throwing team, that's saying a lot!
My guess is he most certainly can turn out to be a #1 WR, but that it's far from a lock that he will. I can say I'm fairly certain he would be a solid #2, if not right away, but that he has other upsides as well. He had 34 Punt Returns for over 300 yards this year, after all.
Bottom line-I'd be thrilled to draft him in round two.