i'm buying a 10D, and i'm just wondering how it will work in cold weather. i want to bring it skiing a fair bit. i know my old canon S30 point and shoot camera worked just fine in -20 degrees, the only problem was that you'd have to be very careful not to breathe on the lens, and you'd average about 80-100 shots on one 570mah as opposed to a couple hundred. does anybody know any other detrimental effects that i might encounter when using the 10D in -20 degrees? also would having the vertical grip that allows you to use 2 batteries simultaniously be essential, because it would reduce the individual drain on each battery, or does it even out in the end by how much charge you get out of each battery?

i think i once read something about someone being afraid to freeze their CMOS sensor, but i know i've frozen my S30 many times while using it, and it hasnt hurt it at all, so would this be an irrational fear, or should i worry about it?

Will's probably the man with the answer, so some advice please?