This is pretty sweet if you are waiting for GTA 5 like most of us. This guy went into LA on his bicycle to see if he could find the same locations in the game. Seems like a lot of work, but still cool. Game releases September 17th, 2013.
Many places look totally spot on. At least to someone who doesn't live in Los Angeles, which serves as the template for Los Santos. No doubt, residents of LA will note significant differences (at least to themselves).
Somewhat like how residents of New York love to pick over Liberty City the same way in Grand Theft Auto 4.