Yelp! should tell you if a restaurant offers free refills or not.
They tell you if restaurants serve alcohol, take reservations, deliver and are good for big groups or kids. But there is no information on whether or not the restaurant is going to nickel-and-dime you on soda refills. For a thirsty dude like me, that information can be just as important as if they accept VISA.
P.S. If you want to become my friend on Yelp! or check out my sometimes scathing / sometimes adoring reviews, you can find me here.