The below pic of Alice Eve, Zachary Quinto and an unknown fella popped up over at Trekmovie.com. As you can see, Eve's character is wearing a similar sort of flight suit to Spock, implying that she's on his side, and from there it's not too much of a stretch to assume she'll also be a member of Starfleet..
Although that's a lot to draw from one set pic, It's definitely a safe bet that she won't be a villain at least. So who will she be? Initial reports indicated that the character will be new to the canon, but that hasn't stopped fan speculation, and some guesses have included Yeoman Janice Rand, Nurse Christine Chapel, Lt. Marla Givers, Dr. Elizabeth Dehner, Dr. Carol Marcus. What do you guys think? Keep in mind, they all swore blind Cumberbatch wasn't playing Khan too!