Despite legal challenges to Psion's netBook trademark, Google's playing it straight: there will be no use of the term in ads until the sugar's shaken out. In a response to a request to lift the ban, it revealed that it banned that particular AdWork directly at Psion's request. From Save the Netbooks:
Please note that we received a complaint from the trademark owner of NETBOOK. In their complaint, the trademark owner stated that they are the owner of the mark and that its use in certain advertisements is not authorized. ... If you disagree with the trademark owner's assertion of exclusive rights to use the trademark, we encourage you to contact the trademark owner directly. Google is not in a position to arbitrate these disputes.
Google rejects review of AdWords "netbook" ban [Save the Netbooks]