The biggest issue (as it usually is) is to find the funding. Keeping it vendor agnostic without tapping into marketing budgets of vendors would be difficult. Could we pool all of our Starwood points to get some space someplace like Phoenix in August, or Portland Maine in January?
A steering committee should be assembled to investigate. Maybe a university to secure space given that this could be the academic Mindmeld of Identity, or the Identity Stew.
It bears further investigation... And a solid sponsorship model. I'd throw some points at it...