Who is this?

I saw this photograph in a picture frame in a store. Obviously, they were selling the picture frame and the photograph just happened to be there. The girl in the photograph is most probably a model, actress or a celebrity of some sort. I wonder who she is.
Who is this girl? - click to enlarge (141 kb).
If you have any idea who this girl is, please post a comment or send me an email. You can also view a larger version of the photograph here.
Suggestions till now:
1. Jennifer Garner
2. Michelle Trachtenberg (plays Dawn Summers in “Buffy the Vampire Slayer”)