They are almost certainly making PC, PS4 and Xbone versions of GTA V.Omega500 said:Have they said why they haven't?
There's a good Pach Attack on Gametrailers where he explains the reasons they haven't announced any of them yet. At it's most basic it's because they (Take 2 and Rockstar) have a lot of money at stake in GTA V and they want the sales straight away, they absolutely do not want people holding off for the PC/XBone/PS4 version as that leaves time for hype/spoilers/piracy to eat chunks out of their potential sales.
As it is, there are 150 million PS3/360s out there right now, they only need a fraction of that and the game is financially sound (it seems to be just that now a day later). Once the new consoles are out a next gen version will no doubt get announced (haven't those published screenshots looked suspiciously good for PS3/360 games?), by that point they no longer present a financial or sales risk to the current gen version.