The humor was really dry and that did make it hard to follow unfortunately. I could tell that many of the voices were done by the same person as well, and that also detracted from the dialogue too. Not to say that I think is was poorly done, just not done well enough to look over is all. Lastly, the script sounded forced a bit, like you (or whoever else was doing the voices) were overacting a little, but I think that's pretty common for most any freelance Flash cartoon involving voices.
Animation wise, I thought it worked well and couldn't find any obvious flaws. Smooth, nice framerate, decent lipsyncing... only, it was just kind of difficult to sit through is all.