Good place to start the discussion. ^^
I wonder, though, if the bright line ought to be commercial vs. not-for-profit?
Being the "owner" of a Googlegroups listserv and its associated website for folks who love to travel to see the gerbils in Bangor is probably different from being a leader at TripAdvisor.
I think being a "leader" on "any" travel website is a bit too broad. Thoughts?