For the past couple of days there have been rumours circulating around the net that we might see a new GTA game by the end of this year. It would seem Rockstar are keen to quash this rumours and have reported to kotaku that there will be NO NEW GTA game this year :-
according to parent company Take-Two Interactive, But there is "no truth" to reports that a wholly new retail game, one on par with the scope of Grand Theft Auto: San Andreas, will arrive before the holidays.
Naturally this does not include already announced GTA's such as Chinatown Wars and the DLC for the Xbox 360
Source : Kotaku.com