Interesting, I just saw this over at the Midway forums and didn't even believe it was legit. There seems to be a lack of detail and some pretty lazy shading compared to the other renders. Well, I guess that shows me.
I always thought of Wonder Woman as being somewhere in the mid to late 30s. It gives her a more mature and wise feel than the other DC heroines, especially her 'apprentices' like Wonder Girl and Kara Zor-el.
The check bones are showing too much, she is too thin in the face. The thin face = not normally used as a sign of youth. If she is young, she sure is starving herself (hey, that kinda explains the lack of musces when you think about it). Then again, it can also be put down to shadows.