Erm, probably 360 since its $199 vs $299 and she can make up the difference with some games.
Edit: Since you seem to favour the 360 you can lend her your games, there are more cheap games on the shelf for the 360 and a wider selection at most stores due to the larger userbase in America. Due to this her total cost of ownership can be lower than the PS3 and the lower entry cost sure helps as well.
Do you know what its like to live on the far side of Uranus?