At a media presentation earlier this week, Sony announced that they will reveal a release date for God of War 3 at E3 in June. Yes, it's kind of silly that we're reporting on when an announcement will be made rather than the announcement itself, but it's God of War 3, so this story exists.
We've heard a lot of rumors that the game will hit in early 2010, with many guessing that a March release makes sense, since all previous God of War games have shipped in March. If true, that would mean the team at Sony's Santa Monica studio will have had three years to complete the game -- with a splinter team working on technology for even longer -- which is a pretty substantial amount of time, and equal to how long God of War 1 took to make.