Haven't read much of the thread, but here's my 0.02c
Don't lose focus. Sometimes by trying to "expand," you can undermine what you've already created.
Just focus on sales data. You can add to that sales data analysis, or sales data discussion, to break down sales in different ways, and a game database that focuses on sales. Reviews, social network, non-sales news? Start VGReviews or VGNetworks or VGNews.
Better yet, pump in MetaCritic averages and Kotaku news, and do VGChartz networking through MySpace or Facebook groups. Why develop all that stuff internally and compete with those sites, when they aren't the original thing that made VGChartz great.
Think about it: in one year's time, VGChartz went from trailing NexGenWars in perceived credibility around the net, to being poised to pass NPD as the premeire NA sales info provider, had they gone through with stopping providing data as they threatened. That came from one thing alone: improving the scope and accuracy of sales data.
"[Our former customers] are unable to find software which they WANT to play."
"The way to solve this problem lies in how to communicate what kind of games [they CAN play]."
Satoru Iwata, Nintendo President. Only slightly paraphrased.