According to an annonymous source, he claims that he recieved an email from Rockstar Games, saying that GTA 5 is in the final phase of development.
The source says he emailed Rockstar to ask them if they would put his face in the game as an easter egg
Here is a small transcript of the email:
"Hi (insert name here),
Thank you for your email to Rockstar!
Nice to read from you again!
We welcome suggestions and send them to our development team. However, this will realize the often time consuming and can not be realized immediately. Especially for GTA V is the integration of new ideas is difficult, because the game is already in the final phase of development..."
The source claims this information is real. If so, I belive that GTA 5 could be released early to middle of next year.