Here is the list of top social games based on rewards. I added the active monthly user numbers, rating and type of reward.

*note: some ratings weren’t available (probably due to not enough ratings) and the numbers are from March 9th, 2009.
It’s interesting to see that the top game according to Inside Social Games rewards money, but does not have even close to the number of users as the others (maybe due to length of release?). Are users looking for money or things that enhance the game (eg. virtual goods/currency)?
Read the original article “Super Rewards The Top 11 Player Rewards in Facebook Games” posted on March 9th, 2009.