Just a couple of things from me.
1. I am a little pissed off that the iPhone 4 has no additional hard drive capacity to the 3Gs. They've made good improvements to the battery and speed but no improvement to storage. When are they going to upgrade from a measly 32gigs? The iPod classics are already 5 times the capacity at 160gigs. There's no way I can fit my entire music collection onto it so I'll be forced to carry round a classic and an iPhone if I want the choice. Hardly ideal.
2. video calling. Its been around since the infancy of 3G and certainly been on most decent handsets in the last 4 years or so. Does anyone use it? I've never had a video call on my mobile, nor would I want to. I only want to do video via webcam on skype. Anywhere else is pointless, really - unless you were trying to conduct some live phone stream of an event (like some peeps were doing at the G20 riots iirc). But even then you'd have to be guaranteed good 3G connectivity and enough cells in a densely crowded area if you were trying to do it from say, a gig or something. I REALLY don't see it catching on with people in the bus having semi-public conversations via video. The privicy of the handset-to-ear method would seem to be more valuable to me. Is there much benefit from seeing the face of the person you're chatting to? You probably know exactly what they look like. What's the point?