I would rank him right next to Reggie Bush because that's all he is. Its not the talent, its the use.
The minute the Bills took him last year, it killed his ff value. They almost immediately started talking about "flex" this and "dynamic packages", etc and you could see it from a mile away; these guys fell in love with his speed and thought (rightfully)they needed to find ways to liven up the Bills' offense. The problem with that is its counter to FF RB success in that its not a situaiton where you get this guy in the game and he becomes LeSean McCoy or Chris Johnson. The Bills just aren't that team.
If you followed the Bills the past few years, you knew because of lack of talent and injuries and the way they really never turned the run game over to one bell cow (and couldn't because they never play with a lead), this was not ideal. Even when Lynch was looking really good, his stats were diluted by the use of FJAX. When they traded their studly O-lineman, that was it: you knew it wasn't going to be good.
Spiller is enticing and teasing. He COULD do the job. But he's one of these guys that is simply in the wrong place at the wrong time, playing the wrong positon. By the time the Bills improve and build their lines up, Spiller will be like Bush; a nice threat that is still relatively young, but the idea will be to get the guy that can run inside and such as the team figures they will be ready for that by then and Spiller will be a piece but not THE piece.
Sigh.Yet another person pigeon-holing Spiller as a Reggie Bush clone.
I'm not quite sure how you can definitively say that Spiller will be used the same way after just his rookie year. Seems quite a bit premature. I know what you've read. We've all read it. I just think writing him off in that way is a big mistake.
Even going back to college, Spiller showed much more willingness to run inside than Bush. And that's been Bush's downfall as a primary runner in the NFL. He relies too much on his speed and, as a result, hasn't been given the reigns in NO. I just don't think that's the same runner that Spiller is. And, given the opportunity this year, he will prove the naysayers wrong. The Bills are just so void of special talent that I just don't see how they can possibly keep him off the field a majority of the snaps.
Just my 2 cents.

Thank you...anyone saying they know how hes going to be used that isn't inside the organization is plain kidding themselves
So basically, 90% of the people that post threads in these forums ask people to give an opinion. And in this case the OP specifically asked everyone to predict the future because that is exactly what you are doing when you assign a future rank to a person. But when someone actually does it, THEN they don't know anything.It amazes me to no end that people can come on here and writes paragraphs being very specific in describing how WHAT THEY SAW translates into a solid tendency and then someone comes behind them and writes a two sentence quip and posts a smiley face sign.
So the guy that tells you they have been watching this team, points out that the team lost its most talented o-lineman, points out that the team lacks talent and Spiller will be 2-3 years older by the time the team becomes relevant enough to be competitive consistently, points out that FJAX is really a whole lot better than people want to give him credit for...all that stuff is just swept away with a flick of the wrist...NOT because anyone offers a counter point..but because the response IS nothing more that "can't predict future...".
YET, the same people that scoff are the same people that SAY ABSOLUTELY NOTHING to the people that just randomly drop one line about how Spiller will be the #20-25RB. If anything, THAT is predicting the future because it states that these people have reviewed all the factors, put together a list, and that is where he fell...exactly...#20-#25.
If you don't agree with my points, offer a counter. Show me why the outlined facts of the Bills over the past few years WON'T lead to the trend continuing. Show me how its all going to turn around and how you come to reason that this kid who is in a bad oportunity situation is going to do what he hasn't done so far. Show me something more than a random response that actually accuses the wrong person of "predicting the future".
In the meantime, here's the real and simpler truth:
If you have knowledgeable people come on here and post good information, we may all learn something from it.
If not, all you're going to see is the people that have Spiller on their FF teams, or are trying to drive his value up, come on here and defend him. And in the meantime, because its not trendy or popular, people are going to completely dismiss the other stuff that is fact and has already been said.