Those who say failures don't affect the 360 sales, I believe they do.
Failure rates are covered up as best can be, to the extent that theres been little in UK news about the 360s failures but a fair few news reports on the PS3 failures. You go into a shop to buy something, you trust the brand, theres no poster saying "this product will die".
The way it's changed sales figures is most likely in a positive way, theres many people who own multiple xbox360 consoles simply because one failed and they had to replace it, or repair was taking too long. the arcade 360 is cheap as anything so it's not out of most peoples budgets to purchase a back-up console.
Not many people will sell the whole lot and re-invest in another console though, especially if they've spent a lot of money on games and pheriperals and have friends with the same console.
So yeah, I'd say failure rates have helped 360 sales a load.
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