If you own the game already, check out your download link to get the v2.0 installer. I'm not sure if all the third-party stores updated it already. Link to the blog post.
They apparently added "ten new foods to the menu, including an all new breakfast menu, exotic menu and rich dish menu". I think some of them are the ones from the iOS version. They improved the performance and music on the Mac version and finally released a Linux version too.
I just installed this, but I accidentally lost my save file in the process... It'll probably be a couple of hours before I get to the new content. Pretty excited to get back into the game, though.
(By the way, this game still hasn't been Greenlit on Steam. C'mon guys, vote!)
edit: just checked it out, 10 new Specialty Menu that unlocks when you reach specific star ratings. I wish these were around the first time I played the game..