Interesting for more reasons that initially obvious is the 3 network's announcement that it wil be selling Apple's iPhone 4.Of course, like all the other networks, 3 is keeping quiet on price. Instead, it is offering a pre-register page to get your name on the list, without any obligation of course.Why should you want to go with 3? Well, according to the company, the network is 'designed for the mobile internet'. But there might be more of an incentive than that. 3 undercut the other networks considerably for iPad data pricing and does have a reputation for going in a little cheaper.Will Apple allow it to undercut with iPhone 4? And if so, will the other networks be forced to respond? If nothing else, it does add a bit of spice to the run-up to the big UK launch. Just Virgin Media to show its hands now - expect that announcement in the very near future.