I understand you can't manually set the color temp on the t2i? I wonder what other folks are doing for that? Do you have to just set it with a white balance card?

Thats about it, pesonally I prefer to set the white balance this way. On my EX1 I have the option to set the colour temp, and do so for the various PPs I use, but 9 times out of 10 I can get a better balance by using white cards. The maual white balance on the 550D is pretty accurate.