I've been playing a lot of Trove recently, and I'm rather pleased. It's only in beta, so it's a little grindy here and there (and bugs to no end), but it is shiny and fun and full of potential IMO.
The best way I can describe it is, "What Cubeworld could have been."
Seems like another MMO to me with a different coat of paint.
I say that bluntly simply because I've played so many MMOs that they either fall into the cliche gameplay department with some gimmick attached or they try to be innovative and don't provide enough content.