I definitely prefer Terraria. For now, anyway.
AND GOOD NEWS!
Terraria fucking works now. Abaddon and I played together recently, and my laptop didn't catch on fire. None of my other games work yet, but we have this one now.
And Terraria now has a video capture function BUILT INTO THE GAME. We could put together a group project from multiple perspectives (if we felt ambitious enough).
So here are my early thoughts:
I'll play Pudd in hardcore mode, while you guys play soft/med-core characters with class restrictions (knight, archer, etc). The world we generate will be Expert mode, because we're badasses. Your job is to explore, mine, fight, survive, etc.. My job will be to gather, build homes for npcs, and heavy alchemy to keep you guys stocked with potions and shit. Keep me alive at all costs.