Sorry I only just seen this thread.....
I too queued up on thurs and got mine too, only took a couple of hours, not too bad at all....
Im such a gadget whore!
Anyway I had a 3g 16gb and got the iphone 4 32gb
The main differences I can notice is the speed, 5mp camera, hd video recording ( i was considering buying a flip, but dont need to now) The screen is amazing, its like going from SD telly to HD telly.
Im now able to classify all my apps and put them into folders of 12, tidies up the menus considerably, and enables you to put more apps on, even the useless ones!
Multitasking is a feature I not even used yet, nor have I experienced any probs in reception, but theres always teething probs in the first few months....
I love the glass on both back and front, anti oil too, to stop finger smudges, and very resistant to scratches..... plus i get 16gb of extra memory, so Im very pleased with it!