Yes, I got Zack and Wiki for less than $7. The game may have the a little wear on it, but the case will be in near mint condition and it will be one of the best deals ever. I didn't spend as much time with it as I should have when I first rented it, so why not pick it up for such a low price?
GameFly is amazing and I highly recommend it to those of you who haven't given it a shot yet. It may take a little time to get new releases, but the arrival times for games I've rented have been excellent (usually within two or three days of shipping) and you can save a ton of money keeping your games (or buying them) from the service. They shower you with discounts and coupons. Seriously.