I'll probably get both. I had PS 2 and Xbox and I currently have PS 3 and Xbox 360. For awhile I thought the Playstation brand was in trouble, but it looks like Sony is getting back into the swing of things.
Plus, there are games I am interested in that are exclusives to either console. I am a big Halo fan, but I'm also a fan of Ratchet and Clank and Hot Shots Golf. Flower and Journey are fantastic games and are PSN exclusives, and there are XBLA exclusives that appeal to me as well.
I won't get either right away, I'll be getting them later in the year (hoping for a price drop).