You see, when some apps with push support find their way to the AppStore and some apps like MAJOR IM messengers out there (Beejive, IM+, AIM) can't, it seems a little bit strange, don't you think? And if you add to this some complaints that sometimes push messages get lost for apps like StarDefence or AP Mobile (which don't have huge load on servers)... it becomes hard to believe that Apple is actually having long "approval line"...
You see, when everybody submits there app all at the same time, the approval line becomes very long. Apps in the app store that have push obviously submitted theirs earlier than IM people did.