I would have to say face 1st ...and then body...but it depends
I saw a few girls walking around town today and thought....great body but then saw their face and thought 'uch'.
Equally I have been in a situation where I have seen a girl with a body that I normally wouldn't find attractive and been very attracted to..
Both the body and face attracts at first but either one can take over but what gets me every time is a girl with a nice smile, friendly and a confidence about her looks or body but not cocky...