Sony Releases PS3 Back-Compat Checker
With the 60GB version now 'sold out', the 80GB version of the PlayStation 3 is quickly going to be the only option for consumers in stores. Besides the hard-drive size, though, the two systems have another fundamental difference: the 80GB unit handles backwards compatibility with software and not hardware. What games work on the two console versions is now a bit trickier. To aid in your comprehension, Joystiq notes, Sony has released a handy online game checker to let you know how your library will fare. Over at Curmudgeon Gamer, they have an examination of a game library looking at both a PS1 collection of titles and a group of games from the PS2 era. Assuming this random sampling to be in any way indicative, it looks like there isn't much difference between software and hardware compatibility for PS1 games ... but PS2 games might not have an easy time of it.
As the above posters have mentioned, Sony removed the hardware emulation to cut costs on the unit and added another 20GB to make you feel like you got something in exchange. The problem (or not depending on how you look at it) is that they increased the price by $100 for 20GB...yea thats not what I would call an "acceptable" cost trade-off. Thus they made the 60GB look much more lucrative for those who care about the backwards compatibility, die-hards, or to those looking for a better deal. In turn the 80GB looks like you get something for the extra $100 to the ill-informed.
Which is precisely why the 60GB model is a better deal. It possesses both hardware and software emulation, thus insuring near 100% backwards compatibility and the ability to scale-up games that work with the software emulation. And it's $100 cheaper then the 80GB version. Of course this is all an attempt to clear the 60GB model out of the warehouses, so they can push their cheaper to manufacture 80GB. Which should receive a price drop by about $100 or so sometime shortly after the 60GB model is entirely sold out. At least it should, it would be very stupid of Sony not too.
And thats the best explanation I can give of Sony's current actions, hope it helps.
"Now you know, and knowing is half the battle!"