In which lies another problem: Unlike real life, building something out of blocks in minecraft gives you nothing substantial. There's some guy out there right now making art pieces out of LEGOs and displaying them in museums. In Minecraft? You're lucky if your crap makes it to a thread on /v/.
I only play Minecraft if it's loaded with Mods. Like Industrialcraft (My favourite), Mo' creatures, Railcraft, Weapons Ect. Vanilla minecraft is quite boring though.
Ever play Tekkit? It's got Industrialcraft, Railcraft, Computercraft, Equivalent Exchange, Buildcraft, more and is SMP compatible. Best mod compilation out there.