Excuse me, but when did Apple ever state that iPhone ran FULL OS X? They said it runs OS X, not that it ran full OS X. Of COURSE it doesn't run the full thing. If it did you wouldn't get the same battery life, and a lot more of your iPhone's 8GB space would be gone to the operating system installation..
What they did, as far as I can tell, is roll it out "ASAP." Everything ran as root, and hence it was locked down. I would be certain that their internal APIs had not matured either. What they've been doing for the last 6 months+ is tidying that up, putting the APIs in place, and firming them up so they can make them public. That's what happens when you develop software! Ideally you lock down the APIs right away, but that's not always possible, and Apple has sold probably 5M+ of these things now, so the odds are that they're comfortable with the decision to roll it out originally, warts and all.
I personally have no problem with any of that. I've been loving my iPhone since day 1, and I can live with the fact that custom apps are 9 months away.
Bottom line, it's NEVER about technology. EVER.
way different apis from the desktop osx => less of an osx than they claimed earlier => requiring more work to polish and document. not a good thing.
and apple rushing things out of the door half-finish, not a good thing either, but may well explain delay in iphone sdk as well as the problems ppl have been having with leopard and persistance of those problems.
the further you delay fixing problems in software the more expensive it becomes and the longer it takes. even worse, it's a vicious cycle to get into.