It was okay.
I guess people realised that you should just go out and get as many kills as possible, because getting the points for the Defense bonuses is easier than protecting the thingy in the center. The traps and speed bonuses weren't that useful as well - for some reason few blobs fell into the traps, and the speed bonuses were lousy, few and far between. Though, nice attempt at a simple and cute defense game. Better instructions and info on the different enemies would have been useful. Maybe more upgrades on the blob-killer itself would be nice for the sequel.