It's simple why the PS2 is still in demand. The Wii is $200 now but for PS2 gamers that want to play 'core' games, my guess is they'd rather own a PS3 or 360. But a PS3 or 360 isn't cheap. Most people bought the PS2 when it was like $200 and it didn't take long for the PS2 to hit $200. It first hit $200 in 2002 I believe. Adjust that for inflation and $200 in 2002 is still equivalent to like $240 today, $60 cheaper than the PS3 slim and 360 Elite price point. Not to mention that the games are $10 more expensive. So even though the PS3 and 360 have been around for awhile, they are still pretty expensive. The 360 Arcade sku doesn't count because it's pretty bones. Without a hard drive, it's only good for offline gaming and if the internal memory gets filled to capacity, you're gonna have to buy a hard drive anyway. Add in the fact that HDTV penetration was only like 46% in the US as of Nov 2009 and there comes another cost of HD consoles: A HDTV. Factor in the recession to all this and well, the PS2 is just not going to die off just yet.
Oh and heres anothing big thing that gets overlooked: PS2 piracy (yes I pointed out the big elephant in the room!) is cake and risk-free. You can softmod it without opening it up or voiding the warranty. PS3 piracy is non-existant and 360 piracy is well, just ask the million live users that got their console banned. lol. And even if the Jasper was reliable and even if I didn't care about Live at all, I wouldn't risk throwing away a 3 year RRoD and e74 warranty. I'm sure many other gamers feel the same.
Going by software sales, it seems like most of the 'core' crowd already migrated to the 360/PS3 but then there's used game sales and piracy to consider. And hell, Madden NFL 10 sold over 800k on the PS2. So it's obvious there's still a significant 'core' audience left on the PS2.
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