Does the Xbox version have the HD theater? If so, then yes, I can understand the frustration. It's important to consider that they simply ran into some hiccups, though. It's easy to make promises and to get everyone hyped up, and it's even easier to realize later on that it'll take more time to get these things to users than initially thought.
Technical issues can arise, bugs can surface; there are so many other reasons that these things aren't on the PS3 yet. That doesn't eliminate the possibility that this speculation is correct, granted IW is heavily influenced by Microsoft (and from a financial standpoint, rightly so), but I think you guys aren't considering some of the other possible factors as to why those things aren't on the PS3 yet.