This game was $4.99 the other day on Steam and I bought it not really knowing too much about it. Well, after a week of playing, I can tell you this game is really really really fun. The obvious comparison here is that it is a "new" SimTower, but it's not really that beyond the vertical building aspect of the game.
The goals and mechanics of the game are more like SimCity on a micro-scale. You have to manage water, power, gas, TV, and electrical lines within your tower and also make sure tenants are happy by supplying building services from janitors to security (there are lots of things in between).
The game unfortunately is no longer on sale on Steam but if you add it to your wishlist you'll get a notification when it does go on sale again.