Definitely not TD, but quite fun regardless, and definitely wish it was longer :)
For those having trouble with the final level, I strongly recommend building *just* a series of collectors (should be about three) up to the level with the powerup on it, then get a line of blasters (should take about five) maximally spread out across the highest level you can. This should hold back the ooze long enough to get some mortars in place and some more collectors. From that point forward you've got a foothold and the tables are turned. Good luck!
This game reminds me of the good ol' days of Abuse. Though not as good as Abuse, it's still has a challenge level, weapon and enemy variety, and sufficiently well thought out pacing to make it enjoyable right to the end.