Epicue is an interesting check-in app that aims to make sure the restaurants you go to don't have a massive wait time, and we got a sneak peak at BlackBerry Jam Asia 2013. Users check in to establishments with the app and give the place a red, yellow, or green wait time rating. They can also check into Foursquare, Facebook, Twitter, and BBM at the same time, as well as upload a picture. Similarly, you can take a look at the wait ratings for restaurants in your neighborhoods.
The major caveat here is that the data is only as good as the userbase; having one dude submit last week that there was a long wait time doesn't necessarily help you today. Over time, these places could gather decent average wait time scores, and if partnerships are struck up with chains, maybe real-time data could be farmed up based on how many orders they're processing.