There is massive problem with Gaming industry in which we constatly introduce new devices.what that does is makes the old device feel old and totally takes the value out of it from the consumers mind.
People think the platform are different so they look at them in totally different sense,also they don't like to gives attention to old platfrom and they think of new platform as a new investment
Now you might argue that this will make the users of the early devices feel they didn't get their value and without a visionary guy like steve jobs it is hard to keep it going.That won't happen as today's consumersknows that tech fast changes and that he expects to purchase a new device after 3years as handhelds usually deteriorate beyond that point.
and the point that 3DS goes against nintendo itself as competing to 3DS which didn't happen earlier even though DSi games didn't play on old DS because of camera use but view of the product in peopl's mind remain same.
this is the new way the industry work,nintendo and sony can either take it in and work magic or get left behind..this will eventually also happen with home consoles when the rate of change of graphics go in 10 years time.
for example if nintendo today markets a new mario game as a DS title and puts 3DS only up for sale,after 1-2years every person would have 3DS so then they could slowlly stop putting games on original DS
