Uhoh.... Here comes the head shot debate thread!
I've taken head shots before, since Westtex mentioned it. If they're close, calm, I have a good rest, and they aren't moving around, that shot will drop them. I wouldn't risk it if I wasn't sure though. I've seen deer that have been badly hit in the head, it isn't pretty.
I'm a fan of neck shots. I've never had a deer take a step when I've shot it in the neck. Again though, this has always been on closer shots for me. I'm thinking my farthest neck shot was 65 yards or do.
If I'm not on a rest, the deer is moving, or other variables are involved, the chest is where it's at. Bigger kill zone, easier target, more room for "error". Hit here, a deer is going to die. It may run, but you should have solid blood to follow.
So, it's situational. My "favorite" would be the neck though.
-Jake