I've never managed to get iChat to work properly. Keep getting error messages which annoy me too much to keep trying.
But I'm loving how they've made it look on this design. It's a great idea and with Google Maps to boot, that would be a killer feature.
Not keen on the side view though, it shouldn't (and probably couldn't) get thinner like that.
The front view does look cool, although with the grey / silver colour chosen I'm seeing the colours from the previous iteration of the iPod Nano (the short fat ones) so maybe there could be loads of colours. Which would be nice.