@cky4890: Do you play a ton of games? Can you not afford said games? If yes, Gamefly is for you.
I switch back and fourth between the 2 and 3 game plans. It's great to play a game and send the other back so you have something to play while you wait.
Tip - if you want a title that is coming out in a few days, clear your que and make sure it is the only game in there. My biggest complaint with Gamefly is how the organization of the que never matters. The game that you want can be at the top of the list and high availably, but they'll send you game number 17 for some reason. (Just happened to me with Catherine and Enslaved)
Oh and the turnaround is usually 3-5 days. Most of the time it's 3 days though. And new titles usually come the day after they are released. I use gamefly for my review site and I usually have a video of each game I rent up by the end of the week.