Take time to call your guests to confirm the exact (or close to it) number of people to expect for Thanksgiving. Verify they will be there for dinner, not just dessert. I always prepare for a few more just in case but try to get a better idea so you are certain you have everything you need.
At the same time, check your lists to see who is supposed to be doing what. Then call them to make certain they remember what they are bringing or doing. If there is a problem, no stress. See if you can assign it to someone else. Otherwise, either take care of it yourself or skip it. Remember, this is your event. Do it your way!