Actually, that's all you can do at the moment. "Alpha 0.1" has 36 different block types with which you can build, alone or with another local wireless player. Other features will be built into the game later, as with the main game. Also coming later is a wider Android release.
While you think about whether to try this out, here's a miniature tragedy: That Minecraft-themed Xperia Play phone auction hasn't ended yet, so its new owner definitely doesn't have it in time for Minecraft's release.