Action 4 Life have posted this article which takes a look at Sonys plans for the coming years regarding its consoles and games:
The PlayStation (or PSOne) will only be sold until the year 2005 (which, coincidentally, coincides with the release of the PlayStation 3). Get yours while you can =) Incidentally, the PS3 WILL NOT be backwards compatible with PSOne games. It will play PS2 games though. They have firmly stated that they will ALWAYS have 2 consoles on the market at a time, so when the PS4 comes out, say bye bye to the PS2.