Not only has it all been done before, but it's been done much better.
Like any other TD around, Savage Moon's concept is to prevent swarms of invading enemies to reach a certain point. To do this, the player builds towers; in Savage Moon's case, a list of towers that are decidedly lacking balance and originality. Only a couple of towers are really useful, and they're all fairly standard with nothing creative about them. This is pretty annoying, since the game's difficulty is pretty hard and to succeed the easiest and most efficient method is to mass-produce certain towers.
Still, Savage Moon's core gameplay is slightly enjoyable. You've probably done everything it has to offer in another game, but not on PS3. The game's controls are surprisingly comfortable, and menus are pleasing and easy to surf through. Despite RTSes getting a bad rap on consoles, Savage Moon has the basics nailed down.
Unfortunately this unambitious TD takes a hit in its boring and overly simple level design. There are only a couple paths enemies ever take, which really lessens the strategy aspect of a strategy game. The player will rarely ever have to think about where to build; the game forces the player to build in certain areas or failure is imminent. Similarly, players are required to build certain towers or die. For me, the joy of TD's has always been about the freedom to create my own custom defenses; here, it just feels like I'm following a tutorial that doesn't outright tell me what I'm supposed to do. Some players will enjoy this method of making the game more approachable, but I can't help but despise the simplicity of the game's design.
Not only are the towers unbalanced, but they're dumb -- literally. Towers don't shoot enemies until they "see" them, and unfortunately they have rather poor vision. It can be frustrating to see an enemy destroy your base because a tower didn't feel like shooting at it.
The middling presentation doesn't help much, either. The graphics are a bit bland, especially environments; artistically generic and technically sub-par, there isn't much to look at here. Savage Moon's soundtrack has its merits, and the battle theme is cool, but for the most part it's as uninteresting as the visuals. There also isn't any narrative or text to speak of; and while I'm aware it's not something most players will look for in a TD, it's a lost opportunity.
While Savage Moon has proved to me the Dualshock 3 can control TD's, it hasn't shown me what PS3 TD's can and should be. Hardcore fans of the genre and gamers who've never touched a TD before may want to try Savage Moon out for a few hours of entertainment, but Fluffylogic has a long way to go before the PS3 gets the rock solid TD it deserves.