read this article:

http://www.gamesetwatch.com/2008/06/analysis_what_vgchartz_does_and.php

what do you think?

ok so these are the main points:

Essentially, Walton is saying that he uses a number of high quality factors to produce his estimates, but can't mention any of the retail sources, or companies that VGChartz works with. Well, fair enough. But did you realize that VGChartz estimates can retroactively change by 100% or more based on 'official' chart results?

Firstly, if you were a journalist, you could have cited VGChartz as saying Iron Man was a flop on PS2, selling half as many units - when NPD vibrantly disagrees. In addition, and more interestingly, it shows that VGChartz trusts NPD over their own prediction data by retroactively changing things to better match.

In other words, for those high-selling titles, VGChartz is checking against public data, and they will change their estimates if they are majorly off. Most of the time, they are quite close compared to the worldwide charts. That's because VGChartz is - like services such as The SimExchange - using common sense, Internet buzz, real-time data such as Amazon.com and analyst commentary to synthesize a sensible estimate.

And the amount of concrete data available to VGChartz is low - as is freely admitted in a recent interview, VGChartz had 2-3% of the North American market as a sample at the time, whereas by estimate, NPD might have 60-65%. If this 2-3% was clean and canonical, this might not matter - but how do you explain the big Iron Man discrepancy, if so? Wouldn't VGChartz' retail sources have picked it up too?

Let's be clear. I think the concept behind VGChartz is a wonderful one - freely available data to let everyone see how well games are selling. And it's absolutely true that all data is an estimate - not even major services such as Media Create and NPD get it exactly right. But VGChartz is staffed by amateurs working in their spare time to estimate sales, and while they are perfectly smart, they are much closer to the SimExchange model of estimation than the Media Create method.

"VGChartz can exclusively reveal that first day sales of Metal Gear Solid 4, released on June 12th 2008 in most major markets worldwide, were an impressive 1.3 million units."

The headline actually originally read 1.5 million, but was changed by a not insignificant 200,000 units after publication. Even more surprisingly, the figure debuted just 48 hours after the launch of the game - not a lot of time to compile data from retail sources.

But if I was a writer or analyst trying to extrapolate significant information from the resource, especially regarding those titles which don't chart regularly, given the major discrepancies with other figures shown here, I would not recommend it.

(sorry, but all i did was copy and paste these paragraphs from the article because i'm lazy, but i hope its good enough now)

You're a bit late:
http://www.vgchartz.com/forum/thread.php?id=30508&start=100

its to long.

can you just post the main points of the article

dammit. i'm always late in these kinds of posts

You can try to bring it up again...but the last thread already had at least one casualty.

alright, i brought up some the main points/paragraphs

I was just joking when I said that you could try this thread again.

Honestly, there is 3 pages already....

If you'd like to take part in this debate again...try here...since it is a fresh take on the same article...only via Kotaku this time around.