My own little data point fwiw - I'm using an iPhone 3GS in Perth, Australia on the Vodafone network. The reception is definitely worse than my old Nokia on the same network. I've heard similar things from friends using iPhones on Optus which has a separate network from Vodafone.

I definitely think there's an issue with the iPhone's reception, but it's not so bad that I'd go back to my old "dumb phone".