I imagine the price will drop, fast. Is it worth 45 dollars? Who is to say, honestly, what any game is worth, when you can get the greatest games of all time at a measly 10 or 20 bucks eventually.
Reviews are starting to come out and say roughly the same thing I'm thinking. Looks ok, fun to bash/shoot stuff but has a slow burn at the start, linear levels with a kinda non existent inventory and meh character progression, trite story, somewhat difficult even regular baddies which I think is a positive, and a lot more fun with a partner though the AI is pretty competent actually. Throw in a couple of unfortunate glitches here and there, a highly customizable dungeon creator for a type of hoard mode and an only average length somewhere in the neighborhood of 10-12 hours as a regular playthrough(kind of a NG+ thing too), and you're left with something in the 6-7 range.
I think of the game, itself, as something of a 7, but enjoy playing it with others(and today with a friend finally) because I believe the co-op is done relatively well and the difficulty is there to force you to help each other out.