Firstly, whoever decided on that name for their forum knew they were living on borrowed time. In the old days if you owned a domain you owned it and no one could take it from you. This irritated corperations who pushed to make it legal for them to fill out a few forms and take domains.
Secondly, why doesn't Apple just use iPhone.com? They already have it.
Lastly, Apple is run by black hearted, baby eating, inhuman monsters so they will either get it easily or go to court, ruin a few peoples lives, take everything said people own, and end up with it anyways. Any way this ends Apple will have that domain. So the only choice is whether to give it up easily or run a massive smear campaign about how cruel Apple is then be defeated in court.