Oh hun, I think it's the typical combination of the hairline and the fact that babies just have heads that are a different proportion to the rest of the body than adults. I wouldn't have thought anything but "supercute baby" without your pointing it out. She looks perfectly normal to me.
I once sent a wonderful pic (my favorite) of myself and DS1 to my mom, thinking she'd put it up. End result: "oh, I couldn't possibly show that photo to anyone, his head is soooo big, people will think there's something wrong with him. Have you had is head size measured?" I still haven't quite forgiven her.