QUOTE
Apparently, 10.4.10 created a vulnerability that was absent in 10.4.9, ergo, no updater for those folks
Actually, that's not quite true.
Apple only releases security updates for the highest point version of each release of Mac OS X. So 10.3.8 is vulnerable, but they do not patch 10.3.8--only 10.3.9. 10.4.9 is vulnerable, but Apple does not patch 10.4.9, only 10.4.10. You
must update to the latest point release in order to get security updates.
Mac OS X 10.4.0 through 10.4.9
are vulnerable. However, Apple does not release security updates for them, because it would have to write 10 different security patches and test them in all 10 different Mac OS configurations. So if you stay at 10.4.9, or any earlier version, you do have these vulnerabilities and they will not be fixed unless you install 10.4.10.