I was going to pre-order starbound, but I spent all my money on Toribash. Friend got it though, looks awesome.
I generally play Terraria, Skyrim, GTA 5 and COD other times.
Mostly I play MW3 though, since the Ghosts community right now is full of douchebags.
Skyrim and GTA 5, there's not really a limit to how long you can play, but after a while; something like 300 hours; it gets mind-numbing. Finished all the quests in Skyrim though.
With Terraria, I built a floating teleportation house out of rainbow bricks and I have waterfalls coming down and whatnot so it gets a bit boring after a while.
I actually waste my life quickscoping and golding weapons in MW3, it's pretty sad. If I bothered to transfer some of my clips from my PS3 to my PC, I could show you, but kinda lazy.