Well, "ilounge":http://www.ilounge.com/index.php/news/comments/live-iphone-3g-vs-iphone-comparison-test-results-here/ has a good first review set:

* The White 16GB is going to be much cleaner with fewer fingerprints than the black one. I'm kinda regretting ordering the black one now that I've seen photos. The white one is actually quite cute.
* Some folks are saying that this is really like iPhone 1.1 because other than 3G not much has changed, so if you already have a current iPhone you can wait for the next churn. (For those of us who have lost our iPhones, we are screwed!).
* The best thing to do with an iPhone is to try to get an unlocked one. The plans are really expensive at $30/month if you are a consumer. OTOH, the$45/month enterprise one is at least, just as much of a ripoff as the Blackberry plan. So you are no worse off if you are an Exchange user 🙂
* Sound quality on Bluetooth is better, but about the same as the original iPhone on the headset. The speakerphone is a little louder (important for me).
* 3G network isn't always faster. Naturally, it depends on AT&T's network, which I'm sure is not too high performance. Essentially 3G is about 26% faster in NYC. Wifi is still the method of choice at 2-7x faster than 3G with an average of 4x. In Orange County (who knows where and how that network is configured), 3G about 2x faster than in NYC. So YMMV