Exactly, maintainability also means availability.
Apple was working in secret on an X86/X64 version of Mac OSX since the beginning it was not available yet it was maintained...
It was probably a mistake to do not update the 68k branch as it is where most users are. We also know that the so called Classic users, the hardcore one will never take the PPC route. Jedi tricks do not work on them.
Better later than never though.
Kamelito