Psion, Psion. We hadn't really heard from the British portable maker since the halcyon days of the Series5, but it's back and making waves with a series of nastygrams asserting its trademark of the word "netbook." Psion's legal team followed up with jkOnTheRun, and according to them, it's only going after those sites and companies "making a direct, financial profit from use of the 'Netbook' trademark." (As opposed to profit in kind, we suppose -- did you know our advertisers pay us in toaster waffles and aviator sunglasses? True story.) Psion says it's mostly focused on retailers and manufacturers using the term netbook to sell machines, not "straight blogs" and other sites. Of course, that means next to nothing, since Psion says it'll still go after those sites that have sponsored ads or for-profit links containing the word "netbook" -- including automatically-placed ads and links like AdSense and Amazon affiliate ads that site owners typically have no control over. +10 weasel, dudes. Anyway, considering the widespread adoption of "netbook" in the past year with nary a peep from Psion, we'd say the term is pretty well generic and no longer a valid trademark at this point -- we'll see how it goes when it drags the first heavy-hitter using the term (like Intel) into court.
Disclaimer: Nilay's a lawyer and secret Asian netbook ODM, but he's not your lawyer and this isn't legal advice or analysis.