Some netbook enthusiast sites have apparently received cease and desist (C&D) letters, demanding that they remove the term "netbook" from their pages before March 2009, else face legal action. The letters, which until now have been sent to UK-based sites, claim that the netbook and netbook pro trademarks are owned by the company responsible for the Psion Netbook, a larger version of the company's PDAs that has not been in production for some years now.
While the Psion Netbook (or the Netbook Pro) itself is no longer in production, the company that own the trademark still manufacture accessories for the device. We're still yet to see the content of the letter apparently sent out; a preliminary search for UK trademarks shows that Psion Teklogic hold "netpad" and "nettablet", but the contested "netbook" and "netbook pro" marks have not yet been found.
In any case, the company seems late to the game in attempting to wrench back the terms, never-mind the fact that they're really targeting the wrong people. It's Intel that coined the current use of the netbook phrase - and who own and run the Netbook.com portal.