Yeah only the 20 and 60 versions currently support ps2 games. However all versions can through emulation but why do a full emulation for every game when you can sell the a single game through the psn network and make more money.
Not true. The 80 GB with lesser compatibility still needed one of the two PS2 hardware chips.
The PS2 games like God of War 1-2 and the upcoming Ico that have been released for all models are ports, not emulation.
All models can play PS_1_ games through emulation, but they do that for normal PS1 discs not just PSN downloads.
What he means is that even without the emu chips Sony can write emulation wrappers for individual games that will allow those games to work on all PS3s. This is exactly how MS does it with the 360. Each original Xbox game has a custom written software emulation wrapper that allows it to work on the 360. It is true that UNIVERSAL software emulation is tricky and difficult but on a game by game basis it's actually pretty easy for them.
Sony has already stated thay plan to bring PS2 games to PSN at a future date using this method. The difference between them and MS being that Sony wants to charge for them instead of offering it for free. Note that I'm talking about PS2 originals, not remakes or ports.
I promise that once the PS2 is finally retired they will roll out PS2 games on PSN that will work for everyone. Be prepared to pay though.
The difference would also be that MS would be giving you just a wrapper that still requires a disc, but PSN would be selling you the actual game.
So instead of buying the games again on the psn. It would be more beneficial to get the ps3 with the 2 ps2 chips inside then correct?
You could buy a PS2 Slim instead for $99, but then you also need memory cards (roughly 1 per game you're playing) at $15 each, and a component cable for ~$20 if you want the best picture.