I can’t speak for whether the OSRF has the resources to be a QA group, but I think that collecting volunteers from outside the OSRF to be members is a fantastic idea (Debian is a volunteer organisation, after all; I actually quite like Debian’s web-of-trust organisation in general). I would happily volunteer to be a part of such a group, and would also be happy to help with managing it if the OSRF does not have the resources to do so.
If there is interest, I can draft a REP that lays out a set of policies and procedures for dealing with orphaned and abandoned packages in ROS (including how those terms are defined) so we can get some more formal discussion going.