A leaked image of a European poster for Grand Theft Auto V indicates the latest in Rockstar's saga will be released in Spring 2013. This is the first time we've had reasonable confirmation of any sort of release window for the game.
There is no indication if this timetable applies to a global release, or if Rockstar intends to stagger its release dates. Grand Theft Auto IV had a simultaneous release in Australia, Europe and North America, with Japan receiving the game 6 months later. The images bear a European ratings logo on them, so there's a chance the rest of the world could be getting the game some other season either sooner or later.
The only system/publisher logos on the poster are for Xbox 360 and PlayStation 3. It appears as though - for now - there are no plans for Wii U. More GTA V news is set to arrive in November.