PS3 backward compatibility: Less than 100 percent
It appears that not all PS2 and PS1 games are playable on the PlayStation 3.
One of the advantages of the PlayStation 3 that Sony's been touting is that it's fully backward compatible with games for the PlayStation 2 and even the original late 1990s-era PlayStation 1. In other words, there's no need to scrap your collection of old games: you can still play PS2 favorites such as Grand Theft Auto, SOCOM, and the upcoming God of War II while you wait for those franchises to make their inevitable jump to native PS3 versions, replete with all the attendant high-def eye candy.
Or, at least, you can play most of those PS2 games. Reports out of Japan, where the PS3 went on sale on Saturday, indicate that a variety of audio and graphical glitches have cropped up on some high-profile PS2 games, including--according to gaming blog Kotaku--Devil May Cry, Tekken 5, GT4, and Silent Hill 2. Reuters cites Japanese newspaper Sankei Shimbun putting the total number of incompatible titles at "about 200." For its part, Sony has pledged to address the incompatibility issues with downloadable software updates (one of the advantages of the PS3's built-in broadband support).
To put the problem into perspective, 200 titles (if accurate) represents only 2.5 percent of the more than 8,000 older PlayStation games in the back catalog. And the PS2 had some of incompatible titles as well: at least eight games made for the original PlayStation never quite worked properly on the PS2. It's also worth noting that, on our PS3, we were able to run two PS2 titles we had on hand--Shadow of the Colossus and Star Wars Starfighter--with no noticeable issues at all.
Compared to its main rival, the Xbox 360, the PS3's less-than-total backward compatibility still comes out ahead: the 360 currently supports more than 200 older Xbox1 games (full list) out of a total of around 700, with Microsoft periodically expanding the list via downloadable emulation profiles. Meanwhile, the plays all of the company's GameCube titles, but we wouldn't be shocked to see a handful of incompatibilities crop up on that console, either.