I did some snooping around. I think there's a bug in System Update.
My Bios reports my TP at 3.19. I'll update this now but the behaivor I'm seeing is a bit wierd. One problem is that my embedded controller version was at 2.04. I've updated that. The BIOS does report the correct machine type. So does the ThinkPad Configurator. So these are reading something different than System Update.
At some point, System Update just took over the whole version process. And I got stuck with mismatched versions of system files. And I haven't had it update any files for more than a year. I did find one problem with SU.
OBSERVED PROBLEM:
SU obviously records the system type in some other file. I chaned the Runtime/MTM registry setting listed in the previous post. I then ran SU. It gets to about 10% and says "no updates for you" just like it has for the past year or so. Ok fine. BUT, when i close SU, it actually REWRITES the registry setting back to '0123456'. That seems like a bug.
I did the same thing with PC Doctor. PC Doctor is reading the system type from where ever SU does (not Bios, Not registry). But PC Doctor does not rewrite the registry entry.
So changing the registry value for SU has no effect. Now onto updating the BIOS manually to see what happens.