And according to CNN just tonight (10 Jan 07), the...um...litigation...has already hit the fan. As many have pointed out, the iPhone trademark was originally registered by Cisco Systems, Inc., who has filed suit against Apple.
There had been talk of a deal between the two companies to transfer the trademark, but I suppose that broke down, and that's why the lawsuit is coming about. I personally hope this works out in Apple's favor -- the iBlower or iHorn don't sound quite as appealing.