I use very (very) little voice at all, so I don't think that's going to be a concern for me. What I hope to do is more mobile messaging and more importantly, allow online access to the interesting apps that need it. With GV I can also have voice mails transcribed, so if I know I don't wan to "talk" on the phone one afternoon I can just shuttle everything to VM.
Oh, forgot to mention in the last email. I did pick up an iPhone 4, subsequently canceling my online order - it would have only been delivered around November 17