Regarding Harvin, I'd really like to see him go to a team that exploits his running skills - because in addition to having some nice receiving skills, he's got a nice running style, very good vision, and great burst. IMO he's quite strong in the upper body, but he doesn't have Chris Johnson's leg drive and he goes down very easy on contact, even arm tackles. So by comparison, Chris Johnson, for a small back of somewhat similar size, can run the ball up the middle of the line with a reasonable degree of success.
But I do see Harvin as much like a R Bush; he also doesn't show much lower body power so he isn't consistently able to take it up the middle (except for some draws and mis-direction plays). I think if the team that drafts Harvin moves him around and gets him the ball in space with pitches and mis-direction plays as well as pass plays (similar to how NO uses Reggie), rather than use him purely as a WR, IMO he could be just as productive as a healthy Reggie Bush.
But if he is only used as a WR, then IMO his statistical fantasy ceiling will likely be closer to what I would expect from a good but not elite NFL WR. So when I see Harvin, I see a real 'tweener', which can be either a positive or a negative depending on how he is used. If a team makes full use of his 'uniqueness', I really think his ceiling will be much higher.
I don't care if Kornheiser or anyone else calls him a WR or a RB, I really think he maximizes his potential if he is not used exclusively as either, but rather a good mix of both.