I'm not able to complete all quest chains in Icecrown because zones do not phase. I know there is a lot a ppl reporting this kind of issues.
I have recently completed all quests in the zone before Orgrim's Hammer (if I remember correctly I had progressed after that some time ago but some reset took place?), I have no more quests available, got all dailies and drop item quests...
I have a lot of similar issues like this, for example I'm not able to unlock brunnhildar village dailies, commander kreega underneath ICC is phased out, etc...