tangor - 8:40 pm on Dec 16, 2011 (gmt 0)
You really need to get a lawyer familiar with trademarks, business names, etc. We can't give legal advice. It is quite possible that failing to trademark your domains when they first started will force one to take the "in business since" approach, and that may fail in face of a registered trademark holder seeking to protect their trademark.
The analogy of Ford or Chevy dealers is not applicable, they are franchised by the automakers and licensed to use the product name on their dealerships.