If Plastic Logic can afford to put out a device with an 8.5" x 11" touch screen and wi-fi for $300, I'm going to take a wild guess that all other e-book reader manufacturers will be able to more or less match them. PL only makes revenue off the devices, and I can't imagine them manufacturing (let alone selling) enough to get a better volume discount on the screens or other components than Sony or Amazon.
I.e. I'll wait for an official announcement rather than treat the speculations of a newspaper article as "factual."