I haven't played the game much yet, but if I hadn't read some of the other reviews on here I would have quit already. Maybe next time don't make the first 20 minutes of the games click-through dialogue interrupted by a scripted event. It's okay to break up the intros a bit.
I love it. The only thing that really bugged me was that the sell/upgrade tiles can be clicked through, so if you have adjacent towers you have to get right on the edge of the tile to make upgrades happen. Make upg/sell opaque or move them slightly. Other that than this is all kinds of impressive for a web game.