Some don't have real expressions, some do. Probably depends on who it is, how they take pictures, their mood, etc. I try to smirk or smile or make kissy faces sometimes (I don't show my teeth when I smile though because I hate my teeth). And I did (or tried to do) serious looks in my recent ones with my twin sai, but my camera was dying so I was trying to be quick about it. heh.
Sorry for blabbing.
EDIT: Oh yeah, and the quote is from the movie "White Chicks".
V likes...croissants?