Yes, I do....not only at Christmas but always. A lot of the time the prices are lower on-line then in stores which offsets the shipping costs. I also frequently use my Amex "points" to buy all sorts of stuff for free, as well as for no shipping costs. Shopping on line saves me so much time, that I'm glad to pay shipping so I don't have to get dressed, run out, drive to several stores and lug packages home and up the stairs.
I run a business from my home and I'm on line all day long anyhow, so it's a breeze to every once in a while do some shopping at my computer as a break from the tedium of working.