DIY Thanksgiving
If you'll be preparing the Thanksgiving day feast yourself, now is the time to start preparing and executing your game plan. The Epicurious Thanksgiving Timeline will guide you through what to do and when to do it. Martha Stewart's "The Ultimate Thanksgiving Planner" is available for download (pdf), and is so comprehensive that it includes a "Stain First Aid" guide. If this all seems too overwhelming, The Morning News offers a slightly different take on the matter.
If you haven't already, one of the first things you'll want to do is buy a turkey. The Cooking Engineer's Guide to Buying a Turkey is a good place to start. There's still time to order a Heritage Foods' fresh American Bronze Turkey. Or perhaps you'd prefer a Turducken. Turducken is a boneless chicken stuffed into a boneless duck stuffed into a turkey.
Cook's Illustrated's Turkeyhelp.com is an excellent turkey resource (registration required to access some sections of the site), including recommended kitchen equipment and an illustrated carving guide.
You may need some help calucating turkey cooking time.
Have you considered frying your turkey? You'll need a turkey fryer, and I'd recommend a fire extinguisher, good for preventing a major turkey frying disaster.
Before your table is set, you'll want to get to work creating the "classic" Thanksgiving centerpiece, the aluminum foil turkey.
Don't forget the wine! Thanksgiving pairing tips.
Dining out on Thanksgiving
If you don't plan on preparing Thanksgiving dinner yourself, or if at the last minute you discover you have a still-frozen turkey on your hands, OpenTable has a list of restaurants confirmed to be open and accepting online reservations for Thanksgiving dinner. Save yourself some time and phone calls by searching all participating restaurants at once. NYC, SF
Manhattan User's Guide list of restaurants open Thanksgiving day.
NY Mag's list of restaurants open on Thanksgiving day, and their recommendations, as well as a list of caterers available to prepare, and in some cases, deliver (!) your feast.
Citysearch San Francisco's comprehensive Thanksgiving planner, includes restaurants open, caterers, and take-out turkey.