Patently Apple reports that, more than 3 years after Steve Jobs announced the iPhone on the stage at Macworld 2007, Apple has finally secured the trademark:
iPhone is a registered trademark of Apple Inc. – officially as of Feb 09, 2010. The registration number 3,746,840 covers International Classes 9, 28 and 38 which are presented in this report for clarification.
This follows a very public back-and-forth with Cisco in the US and Comwave in Canada, who were marketing VoIP products under the same name.
Round 2, of course, will be for the iPad trademark, though they believe Apple's position there may be stronger than widely believed.