I found that some features (namely, MBGP) are not moved from the 11.1CC train to the main 12.0 train; and you will need 12.0T for them. :-)
I beleive you're confused here, though this thread is defintely more appropriate for the Cisco NSP list.
(When will software/hardware implementations be fast enough to build an [I|routing]OS that is modular - so you can add the features you want without having to load all the crap you will never need? The question itself may be moot, since no technical support group could provide service for such a wide variety of installed systems... *sigh*. )
This is clearly a vendor/implementation issue, not an operational or standardization body one. FWIW, I do agree that more "non-monolithic" approaches will provide better reliability, as do _many other folks. -danny