Though I did use Carbonite for a great duration in WotLK, I'm sticking with the buildt-in questhelper during Cata for a couple of reasons.

- It's more memory-efficient
- Helps keeping the UI clean
- It's always up to date

I do miss the zoomable map, though, even if it did tend to mess up or remove the map artwork in favour of the minimap-view when zoomed in.