The prevaling logic for trading Henry seems to be that his trade value is at it's peak right now. People seem to be forgetting that a corollary to this is that he's also the most valuable to OUR TEAM right now.
Henry was the only consistent player on the offense last season. Why would the Bills get rid of their best offensive player in the midst of rebuilding the offense?
The "might as well get what we can for him" attitude is defeatist. Anyone who would rather take a gamble on WM and a draft pick is implying that the only way to win this year is to take a chance and hope it pays off.
If WM plays well, there is probably little hope that we will be able to keep both backs after next season, but I would rather have them both on the Bills and be able to choose the better of the two. Trading Henry for a draft pick is only a good move under two conditions:
1. we can still get the player we want (not a guarantee in this draft)
2. The player turns out to be a star (not just good).
There is no way of knowing if either of these will be true, let alone both of them.