Ain't bad..
But there's so many things wrong with the game that they kind-of outweigh the good things.
Well, let's start with the good.
I actually like the character designs a lot. I don't know what it is, but I think the simplistic look is a good approach. It just kind-of works.
I like some aspects to the gameplay. That "Pump D!" part got some blood flowing. It was a pretty good idea for the rail-cart parts.
Let's get to the bad.
Playing the game is where the problems flood in. Yikes. Bad Coding here and there, and frustrating controls. That cart/gun part has a MAJOR flaw; the gun is too long to reach the little bat baddies at times. It's extremely frustrating when a horde of them attacks you UNDER the gun. You just can't reach them at all. A smaller turret might have worked out better.
I don't like the animation at all. It's shamefully lazy. You couldn't animate this extremely SIMPLE character and make him look like he's walking? He looks more like he's shuffling. What's up with that? If ANY animation in the game is going to be good, it NEEDS to be the animation of the main character. That's a CRUCIAL part in making a game great, even if it's just an experiment.
Plus, blur filters do NOT always equal actually animating. C'mon.
Finally, the Music (or lack thereof!) makes the game feel empty and soulless. And that annoying scratchy film loop nearly drove me nuts. Couldn't you just borrow some suitable music from the Audio Portal, or even Flashkit.com or something? Yikes.
Overall, a lot of things can be done to improve the game, but I like where you're going. I'll give it a 5 for being on the boarder of good and bad.