Call me crazy, but I think that the fact that this is a weak draft makes our bargaining position better.
Think about it: if there isn't a clearly defined top-5, then for a team in the middle to end of the round, it comes down to need. They will want to trade up just to make sure they get that #1 player at the position they need most, be it QB, LB, whatever - that player will become all the more important to them.
San Diego might be a good example; they are close, now that they are doing well. Let's say thay feel they need a certain position above all others - that there's one position where if they had the right guy, it would get them to the next level of the playoffs. And let's say it's linebacker. Well, they could look at Derrick Johnson and say, "that's the guy!" And knowing that he won't be there when they first pick, couldn't they think that it would be a good deal to give up something to get our second-overall pick, and ensure that Johnson held a Bolt's uni in the first half-hour of the draft?
Now that's just an example - it could be any team hot for any one particular player over all the others at a given position. But you get the picture - isn't it feasible?