Well, apparently the deal is going through. We don't yet know who is trading for Evans. Arizona and Baltimore have been rumored to be interested. While it goes against the Colts' recent history, I wouldn't rule them out given that Manning has about 5 years left. A team like the Bears, looking to leapfrog the Packers, could be another suitor. A dark horse entry could be the Carolina Panthers, who just lost their #2 WR to an ACL tear. In short, there are a number of teams who may be interested in Evans.
The question becomes what is Evans worth? Yes, we'd all love a first round pick but that's just not going to happen. A bidding war would help, though I wouldn't count on that happening. Given that this is a unique year - teams haven't had much opportunity to bring new WRs up to speed (couldn't help myself) in OTAs/training camp - I can see teams giving Buffalo a little more than in a non-lockout year.