In a recent interview with investors ( find more data here on Gamasutra ) Gamestop executives claim that GTA4 did double hardware sales week to week.

That's not exactly what NPD April seemed to hint and in this case we have to believe Gamestop as they have their real sold numbers.

Makes you really wonder about those NPD April numbers... 

Gamestop told one person that they had just picked up the last copy of Halo 3 that day.

Gamestop then told another person that same thing... an hour later.

Hooray for Gamestop's intergrity! 

Gamestop != 65% of market != 30 years expert knowledge

Just as a note ...

Suppose you had sales that were slightly lower than you would typically expect for this time of year at 35,000 units per week for the first 3 weeks of April and then Grand Theft Auto 4 causes a 1 week spike to 70,000 units ... This would mean that the montly total would still only be 175,000 units and Grand Theft Auto 4 caused a week-over-week doubling of system sales.

Gamestop hardware sales equal less than 10% of the entire market. Hell it's probalby less than 5%. The big sellers are Wal-Mart, Target, and Best Buy. I doubt there numbers really affect anything. They could sell out of all the shipments they got when GTA IV released and still it would give a significant overall increase.

I mean I love the enthusiasm and we all are surprised at GTA IV's minimal effects but this is just sad.

what was marchs npd for ps3 and 360?

Considering that far more retailers than just Gamestop sell the systems, and we don't have a hard number to pin on the sales of the two systems at Gamestop before or after the release of GTA 4 this means nothing. NPD tracks many different major retailers and this is just one of them giving qualitative data. Even still, NPD never claimed there was no spike after GTA 4. They claimed it was not as big of a spike as you would expect. For all we know they had both systems having sold 90k the week before GTA 4 and then sold that many again in a week.

In short, you have done nothing at all to contradict anything NPD has said.

Makes me wonder how you fail to realise that Gamestop is not the only shop in America to be honest.

Actually, the Gamestop statement is very much inline with the NPD weekly numbers.

http://www.vgchartz.com/forum/thread.php?id=26962

Even if gamestop's data horribly conflicted with NPD or VGC it still doesn't change the fact that they are a single specialty store and they only account for a small portion of the market. Stores like Walmart, Target, Best-Buy, TRU, etc, etc.. all have far different customer bases and would be expected to see a different sales trend, so you can't just assume it was the same in all retail chains.

So no this doesn't make me wonder about the NPD April numbers at all, it makes me wonder whether or not you gave this any serious thought before jumping to conclusions based on a tiny blurb from an article.