Well, for example, the way Concourse Z is structured on MP, the concourse is a main 'forum' and each product gets a 'sub-forum.' That makes it the 'longest' forum on MP's main forum page.

I always thought that looked kind of gaudy.

So that point goes to things like the structure.

And beyond that sort of formal structure, I think it makes the most sense at the outset to just create the forum and then allow the forum to evolve naturally. Don't set up 'master threads' for existing or known tools. Don't set up 'store fronts.' Don't limit what can be talked about if it is a tool or service and related to travel. Keep the rules as loose as reasonable: just allow any tool or service that is travel related to be talked about, and linked to by any flyertalker. Let the posters decide what they want to talk about and see what evolves. If the owners of the products and services want to participate in the discussions, great. If not, let the posters talk about their product in their absence.

And while booking and bidding engines are clearly travel tools, they already have a forum: Online Travel Booking and Bidding Agencies.

So obviously online booking/bidding threads would be moved to online booking/bidding. Hardware and non-tool technology would be move to Travel Tech, etc. What will be left will be the travel tools and services that Flyertalkers want to talk about and use all in one central location.

Should all be pretty obvious when push comes to shove.

The ONLY issue that I personally think is grey here are hybrid commercial/Dos like the mega seminars and the megados and the award things. To me those are tools or products and belong in a travel tool/service forum. The ROI is in knowledge or comped statuses with community as a side benefit rather than the core reason for attending. But that's ultimately going to be a call for the moderators in places like Cbuzz where the posts live now and/or the mods of the new forum, should it come to pass.