Huh? I must be really slow. I didn't play with my first Barbie until I was 47. But boy, was she hot hot hot!
Teen girls. Cell phones plus lots and lots of minutes. Slumber party type games (ex, twister) - what I mean is more social vs solitaire games. Electronic games (just not FPS). Teen girls are actually pretty divergent. Yeah, the stereo type is they are learning to shop, dress up, etc. But most will form hobbies just like the guys: fishing, biking, sciences,... It's actually harder to buy gifts for a teen girl in that you have to take the time to discover what she is really interested in - which can be harder than pulling an alligator's tooth.