Releasing early and often is good. Pushing that software on people who didn't choose it is not. I feel like there should have been a "Try Unity" button at the Ubuntu installer so people like me could just wait until it's ready.
Maybe I'll be happy with Unity in two years. But in that time I'll have to suffer stuttering, lag and the whims of armchair UI theorists who think Alt-Tab should jump workspaces by default.