GTA V won't come out before September Next Year. Some people said it would be March, but R* would be really stupid to do that since it would steal Max Payne 3's show.
Gamestop listed it for the 22nd September 2012, but they also had it on Febuary 17 earlier this year - So we just have to wait.
Since both games are almost a year apart, why not get both? ;]
Im getting Saints Row - The Third when it comes out, maybe even going to pre-order it when I get the money until then. And GTA V, damn - Of course I am going to get it.
I got my Xbox only becuse of GTA IV.