I have been using this to level faster to 80. No need for it if u prefer to take your time and enjoy the questing along the way:)

Download at:
http://wow-pro.com/addon

It is working nicely with Carbonite addon.

Cheers

I've tried it, I downloaded the latest version but it didn't load a guide for me.

Can it be that I need a specific version (which one do you use Tenderleaf?).

I tried Zygor in both the latest and an old version. The new one didn't work at all and an older one wasn't accurate for WOTLK 3.3.5.