Nobody with a T2i for video should feel like they have an inferior piece of equipment. Even though (back to the original question) they aren't weather sealed, you can get REAL weather sealing for them in the form of either a plastic hefty bag style rain sleeve, or going all out and getting full weather protective cases.
The T2i and T3i are absolutely fantastic cameras for video - weather sealing or not... and if you do decide that you NEED weather sealing, and can only afford either of these cameras, go for a Pentax like a K30 or an older K-7, since they are fantastically weather sealed and offer video quality that is right up there with the Rebels.