Texrat,
Hello! As you can see I am a newly registered user on these boards. As my user name suggests, though, I have been lurking for some months. I am a long-time casual Zaurus user, starting from the 5000d to the C3000. I've since moved on to a Sony UX, but am now awaiting an N810 to replace it. In case you are not already aware, oesf.org already has regional subforums for Zaurus user groups. With the exception of Europe, their groups never seemed to gain much ground. Still, it may be worth contacting their moderators to discuss what opportunities exist for collaboration.

I believe the greatest threat to the regional user group concept is the chicken-and-egg syndrome. If people do not see others signed up in their area, many will assume no other like minded users exist in their area or have any interest. Following this flawed logic makes it unlikely that the searching user will sign up for the regional group. And so the cycle continues.
Perhaps a solution would be to tweak the ITT forums profile "Where you live" field with a drop-down list of locales. Based on locale, and with the users' permission, "skeleton" regional user groups could then be formed. This may lead to users contacting each other and starting the process of forming the physical groups. I have no idea if the necessary features are even available with the vbulletin system, though.

And now I am seeing so many opportunities for geolocation tech that my head is spinning