I don't think that's a behavior that is just for "starter" quests. If you are coming towards the front gates of Orgrimmar, turn left towards the zep tower and near there is a troll standing by a large boulder. Usually with the "Quest-ion Mark" hovering over his head. This troll begins a timed quest called "Need for a Cure" (
Need for a Cure). I did this quest a couple of weeks ago (with a level 23 warrior), and was a bit surprised that it wasn't on a timer any more, having done it with several characters before this. I was about half done when, for some reason, I opened the Blizzard quest log. BAM! There was the timer, merrily counting down to zero and the failure for this quest. Now, I didn't have to worry about it as I'd done this quest before and did it right away, but.......... What about someone that is new to WoW? They might not know it's timed even though there is a reference to it being a timed quest in the dialog when you pick it up.
I haven't, as far as I know, done any timed quests since then so I don't know if this is just for "low-level" quests or not.
Also, as I understand it, the problem with Carbonite's quest log not picking up quests is for "starter" area's. I'm pretty sure Orgrimmar is out of that area. But, then again, when (or where?) does the "starter area" end? The above mentioned quest is level 9 with a level 7 minimum, and I always thought you were done as a "starter" when you hit level 5.