The National Trust for Historic Preservation has released their list of 2007 top distinctive destinations. A favorite of mine, Woodstock, Illinois, made it this year. See Groundhog Day.
Unfortunately, I haven't been to any of the others, but will try to put them on my itinerary this summer. Others include Charlottesville, Va., West Hollywood, Ca. (well I drove through it on our way to the end of 66), and Chatham, Mass.
I'd be interested in finding out what others have to say about these places.
To find the whole list and writeups:
Keep on Down that Two Lane Highway. --RoadDog