This blog which i have clipped here has a short but to the point post.
It outlines how you can make huge strides with your leveling in world of warcraft and also supplies some great links to different resources and reveiws of Zygors Guide. There are videos that are made availabel of the actual guide in use which is a great help to those considering using Zyor Guides. These vids show the the guide being utilised not only with an Alliance character, but also with the Horde.

This is just a thought here, on my server the horde always pound the alliance,l lol and when you look for a guide for WOW, the marketers seem to target horde players! Does this mean that more horde players utilise guides such as Zygor Guides more than the Alliance and does this account for the horde's better game play. One thing is definite, these guides are used more by the Horde than the Alliance and i actually do think that it is down to those guys using such guides as Zygors 1 to 70 Alliance and Horde Guide.