Well, I was about to skip right over this film, but it's a good thing I stopped and gave it a shot.
I'm not sure if I've seen any of your other work, and frankly, this was quite a bit better than I was expecting.

Your animation is smooth, although the fighting could use some more speed and force behind the punches.

The set, while just a couple of walls and a floor, is very detailed and textured. If there was a bit more debris and set dressing, it'd be perfect. Your camera work is great, lending emphasis and style to showdown. Oh, and the use of the "Angry Batman" head was great. It was a fantastic way to highlight the over-the-top nature of the film, and lend a bit of good humor to the normally scowling and brooding hero.

Perhaps the weakest area of the film is the voice acting. The opening monologue doesn't come off as that dramatic, and the near repetition of the "...Batman's here," along with the delivery, stood out in an unpleasant way.

Sure, it's not much more than the typical 'Batman vs Villain X' short, but it never tries to be. It does the role given it well, and while it does have a few rough edges, it's polished up fairly well. Good job.