Not true, Alltel has a massive GSM roamer network out here in the West from when they acquired Western Wireless... True, all their own customers are on CDMA, but I'm betting T-Mobile and AT&T would love to have that network that they keep having to shell out large amounts of cash to have their customers roam on for their own...
I personally want T-Mo to pick up that chunk of Alltel at least, but that's just me. :P