I am a huge fan of Nikon for photo, BUT for video Canon blows them away. Id stay away from sony. I support this because of lens availability(to my knowledge). Canon and Nikon offer a much broader selection of lenses. The Canon T2i is very good. Id buy a T3i because of the flip out screen.
One problem with all DSLR cameras is that the recording time is limited to 20min??? This means that you can't film a live event in the future such as a concert or play. You will record for 20min then it stops and then you have to record again - yes even if you have a 32gb card. Also with long events(to my knowledge) there aren't any ac adapters that will give you constant power.
I know you said you are doing short films n what not but I wanted you to be aware of these constraints.
If you get into fast action, there is always the rolling shutter problem as well.