I have a well-known hatred of VRG, and the biggest reason for it is that they retroactively changed the nature of the world. Lore was altered, in some cases radically, with no attempt at explanation. They changed how the setting works and ignored the fact that they changed it. It is the opposite of respecting the material you are "adapting". They didn't expand it, or re-explain it's history. They flat-out ignored it and made a new setting with similar names and a horror theme. It might as well have been Innistrad (which I would have preferred), and I have not trusted WotC with their own settings since its release. The fact that some people like the new version is irrelevant to my concern, because it's not about popularity. The only one I think they actually did do a good job with since then was Planescape, and I'm still blown away by that.
Don't do that to Greyhawk, or any other setting they touch. You don't have to blow up a setting to add new stuff to it.