After playing World of Warcraft for 6 years, I find it hard to pick up another game that will be a huge time sink and Minecraft can be a pretty big sink
That said, I've pre-ordered SW:The Old Republic even though they have yet to release an official date for people in the "red zone"
Back on topic, I've seen some very very impressive things done with minecraft, it certainly has great potential with it's sandboxing.