Sony has not announced an official release date for Sly 4.
it is supposed to be released spring of 2011
12th of October 2011
It is coming out august 18 2011 
The release date for Sly Cooper Thieves In Time wasn't announced yet. If you hear or see in any website that the release date for Sly Cooper Thieves In Time is May 31st 2012, don't believe it, that date is just a placeholder. Sanzaru didn't announced the date yet but they will, probably later this year.
There is still no release date. But if you get all 3 platinum trophies in the Sly Collection, it shows sly cooper on another adventure yet again. Clues will be back, clockwork is rumered to be back again, and all this time travel buisness.Charecters:SlyBentlyMurrayClockworkDimitriRajanJean BisonNeylaContessaCarmalita Montanya Fox
thieves in time . my friend D'von thinks its gonna be called return of mugshot.
As of right now there is no release date. Sucker punch may not even be making a Sly 4. Keep checking back to www.suckerpunch.com for info on it though
no
How long until it is released? It was already released: February 5, 2013 How long between games? Sly Cooper 4 (Thieves in time) was released 8 years after Sly Cooper 3 (Honor Among Thieves) The series so far includes: Sly Cooper and the Thievius Raccoonus (2002) Sly 2: Band of Thieves (2004) Sly 3: Honor Among Thieves (2005) The Sly Collection (a remastered release containing the first 3 games) (2010) Sly Cooper: Thieves in Time (2013) Sly 5 (in development, no public release date)
Sly Cooper: Thieves in Time will be released October 1, 2012. Sly 4 is slang for the next Sly game release and not an actual game title used by the developer or publisher. Even the title Thieves in Time is considered only a working title when they are selling the game for preorders
sly 4 is in prudoction as we speek. it is set to come out feburary 20 2009. it will be on ps3 the ps2 release is set same date 2010.