Windows NT through Windows 2003 provided an SNMP agent and several extension agents
for things like mib-2 and host resources MIB. Vista does not seem to install any extension agents by default, yet the MIB information is still availavble. Have they moved the location of the extension agents or is all the MIB information now in the master agent instead of extension agents?

The extension agent DLLs still exist and are in the same location. But I can't find the
registry entry that tells which DLLs to load. I searched for inetmib1.dll and hostmib.dll
in the registry and did not find anything, but those DLLs are clearly being loaded into
the master agent.