Spiller was considered almost a lock to land with the Seattle Seahawks, simply because of the way the early round picks were supposed to pan out. After all, Buffalo already has Marshawn Lynch and Fred Jackson. One of them, clearly, is going to be traded now that Spiller's in town.
Lynch is the obvious choice, and that would be the best news for the former Clemson star, if only because no one seems to respect Jackson, and ditching first-round investment (read: justification through carries) of Lynch would give the Bills a clean slate.
Unfortunately, it won't give them a new offensive line, which is another concern for folks hoping to land "the next Chris Johnson." Spiller should still be productive; Jackson and Lynch combined for over 1,500 yards on 350+ carries last year, which means Buffalo isn't opposed to
The better option for fantasy owners, though, would have been for Spiller to end up Seattle with Pete Carroll and new best friend Russell Okung, where he would have been utilized in a Reggie Bush-like manner (in theory anyway, and yes, we mean the USC version).
The good news at least, though, is that Spiller can be productive on special teams and, because of his speed and receiving ability, still damaging in the running game without a great offensive line.
Let's set the expectations somewhere in between Jackson and Lynch then: about 850 yards rushing on 165 carries, with the obvious bonus that if your league counts return yards, Spiller could end up as a strong RB2. The one other bonus is that if Spiller isn't given the starting job by the time the season starts, he should end up as a strong value pick in most drafts.