Good posts from Jim & Steve!
A few things I've learned about release:
1) If you put your fingers on the string the same way every time, they will come off the same way. This helps with consistency.
2) There is no such thing as "release". It's just what happens between being immersed in aiming and follow through to conclusion. Like Jim posted, never think release, think "commit to conclusion".
3) You want the curl of your fingers to be close to the same both before and after the string leaves. Learning this helps avoid plucking. The lady Korean Olympic archer is a good example of this. (I can't remember here name right now)
4) If you are thinking about your fingers (or anything else) instead of being totally immersed in aiming, you should go to the blank bale and the bridge to take your "commit to conclusion" to the subconscious level. As Steve posted, first conscious, then enough repititions to take it to subconscious.
Hope this helps,
Allen