Thanks for all the responses. I have created a wiki page to track this proposal: http://gcc.gnu.org/wiki/cxx-conversion/gc-alternatives
It is also indexed from the main improvements wiki: http://gcc.gnu.org/wiki/ImprovementProjects Given the number of choices we have in this proposal, I've added a table that keeps track of how popular each of the different choices are. If you care about this topic, please respond, and/or update the wiki with your "vote". So far, the clear winner is pool allocation, followed by manually-implemented GC marking and reference-counted pointers. We still have no clear idea of what style of PCH people prefer. Thanks. Diego.
