... Your general animation style is very unnerving, you mix extremely high quality animation and drawings with significantly lower stuff, as well as mixing completely different styles of drawings (there was some hand drawn stuff there that looked very strange) and it's specially weird to see 3D buildings mixed in with 2D animation in the manner that's done in this cartoon (reminds me a lot of the 90's Spiderman cartoon). It's not necessarily a bad thing, but, as I said before, it's unnerving.
The animation "frame rate" also seems to change during the clip, sometimes "100% smooth", other times "Speed Racer smooth", which also leads to a very different style than average. But, truth be told, all-in-all that was very, very good, rivaling with some of the best flash animation out there.
For the rest, the general sound quality was high (good voice acting + music, though some effects would have been nice, albeit unnecessary in a introduction), the flow was also good, but the premise and story seemed a bit, well, clich... On second thoughts, I can't really judge the story and premise since this is a small clip and it just wouldn't be fair. =]
So, in conclusion, nicely done, that very good stuff, even though I did find it somewhat unnerving.