The ban on video game consoles was in 2000. The ban is not strictly enforced, which is why one can find the products from time to time in the mainland. The PS2 was even released to China in 2004 and failed miserably thanks to Piracy. The Product manufacturers (Nintendo, Sony, Microsoft) choose not to ship to china because they know they can't make the money.
Credit Nintendo for finding a profitable video game system without requiring special service fees. Also, the Chinese government treats non-Chinese companies different from Chinese companies. iQue is a company that was formed by nintendo, initally to be a subsidary of the company but for tax and legal reasons it is it's own self-operating company. iQue can get government help if they find piracy outbreaks for their system. As far as I understand, Nintendo Sony and Microsoft wouldn't quite get the same kind of help, the cost of finding the criminal and bringing them forth would come out of their own pockets, that they would have to bring the person to the police, and then they wouldn't have the same protections in court. On top of it, the Chinese government would tax the heck out of them because since it would be the product of a foreign company the products would be considered imports even though they are manufactured there. I think iQue can get away with it because it is technically a different product.
With over one billion people, we have to think that Sony and Microsoft (as well as Nintendo with their Wii) want to break into that market, and if they can find a way to do so profitably, they will get the video game ban revoked because it could mean billions of US Dollars per year in tax revenues..