Really cool! Too hard though. I was on "easy" and the other guy fired a LOT of missiles at me in a short time. It didn't feel like there was much I could do.
Also, though I read the directions, I kept trying to click first on the building I wanted to install, and then on the construction site. The way it actually works seems backwards to me. Or maybe you could make it work both ways?
Still, it's a very cool concept and I'm sure with more practice I could suck at it less.