Honestly I would say she should get a Wii. All my female friends ended up choosing the Wii after trying all 3 (I had all 3 with most of the best games until recently). Women tend not to powergame, and if you don't play a ton the Wii tends to be the best choice. With Nintendo games, Wii Fit and other choices the Wii seems sort of custom made for the casual female audience among the top 3.
2nd choice would be the PS3 for Blu Ray support, Little Big Planet, Buzz and a lot of other casual friendly games. I can think of a dozen PS3 games with pretty wide appeal (plus I have yet to meet a woman who isn't really excited about home when I show them the trailer, ditto for LBP at that). If she likes Resident Evil I would bet anything she would enjoy Uncharted and possibly even Heavenly Sword. There are a lot of great only on PS3 adventure games. Ratchet and Clank is another great example (and there will be a new full release in 09) plus Flower and a lot of great PSN games.
To be honest, as far as female gaming goes, the only game of interest I could see coming to the 360 soon is Fable 2 (I have yet to meet a woman who sees Gears of War, Halo or any FPS and says something like OMG let me play!). I bet you anything that Fable 2 will land on the PC soon enough, and I also would bet it won't live up to the ultra high expectations being sent its way. As I remember the original didn't really live up to its promise of "best game ever" either and was pretty short. I'm sure it will be an 8+ game, I don't think it will be Too Human, but its not worth choosing a system just for that game.
I'm not just trying to be pro PS3, I mean I suggested Wii at number one after all, I just really strongly believe that the Xbox brand is heavily male while the PS3 is more balanced. I really think Home and Little Big Planet will be break out mass appeal IPs.
Another underrated wide appeal game is Free Realms. Its a free MMO designed by SOE for the PC and PS3 that has a ton of different types of content and seems to be made for the same young person/female market the Wii appeals to. It seems lame at first, but if you watch one of the game play videos it looks a lot better then I expected.
I still say the Wii as the first round pick though.
PSN ID: ChosenOne feel free to add me
