Maybe it's because of the string of 90 degree days here in DC, or maybe because some guy on the Metro this morning was wearing a tie with snowmen on it -- but now I'm starting to think about skiing. Are any of the area ski resorts open by Thanksgiving weekend?

I think your best shot, and it's a long shot, is Snowshoe, and trail count will be limited.
In recent years one or two places in NC have been trying to open real early, but often as a one or two day publicity stunt on limited terrain.

I know both Wintergreen and Snowshoe target opening day for Thanksgiving (WTG on the Saturday after, SS on the Wednesday before) but it's totally weather dependent. SS made it on target last season (barely) but WTG had to wait another 2-3 weeks. That was a frustrating few weeks of warm weather and rain. Yet a few years back, they both had great conditions on the target opening day. Let's hope for a cool autumn!