Honestly none of the above!! Obviously all of those help but ultimately its an inner pull that I can't explain. The guy can be nothing I'm normally attracted to. The things you listed just make it better or enhance the attraction.
Physically I like big expressive eyes, curvy hips and boobs, posture with "fertility arch"...personality wise, a girl who smiles, makes good eye contact, and is very confident. A girl who is a 6 physically but very self confident is sexier than a girl who is a 9 physically but is shy and withdrawn.
if you see them, its always physical attraction first.
it keeps you interested to get to know them.
and if you cant see how they look,
then it must be something they said to make you laugh
and get the vibe that theyre cool. =]