I usually do. And do you want to know why??? It's a truly stupid reason.....it gives me something 'Disney' to do while waiting for my trip to arrive!!!
I used to think that it didn't matter much when staying DVC...I had yet to have my requests met to any great extent. But when I went down in Dec, and stayed at SSR for the first time, online checkin actually gave me some usable options. So, I requested close to the bus stop. And that's exactly what I got!!! Walked out the door of the bldg and there was the stop...about 30' away!!! I had no idea what I was doing when requesting anything at SSR..had never even been there before!!!
So, yep, I still do online checkin. I have to checkin anyway, might as well do it now.