I have just been to Phoenix, Arizona and found:
Very few wifi access points, except in the more expensive hotels ($600+/week) and in Starbucks etc (T-Mobile, $10/few hours, other apparently much cheaper longer-term options involve recurring CC debits until you explicitly tell them to stop billing)
Loads of open access points (if you like loitering outside houses
) as usual.
GPRS is about 2x faster than in Europe.
Vodafone PAYG works with GSM, SMS, GPRS. But fax doesn't work (works OK in most of Europe). Roaming via the one GSM network whose name I don't recall ("Cerious"?).
Orange PAYG works with GSM, SMS, didn't test GPRS. Roaming as above.
I don't know if 9.6k data over GSM (as used for WAP) works.
The T-Mobile wifi is capped to 10k bytes/sec but allows a VPN.
VPN is blocked on GPRS (works OK in Europe).
I got internet access at a particular establishment with a T1 which solved the problem for me.
It was an interesting exercise. Presumably, heavy corporate travelling users who need a reliable mobile connection do something else to sort this out. I guess corporate GPRS contracts are better on the connectivity.
America is relatively new to GSM. There are some fantastic Motorola phones on sale, waterproof/ruggedised models which I have not seen before, but none were GSM.
Obviously, make sure your phone is tri-band (900/1800/
1900MHz). I was using a Nokia 6310i for the phone, and a Sierra 750 PCMCIA GSM/GPRS card for the data.