AT&T's first metro-scale network, built by MetroFi, goes live in Riverside, Calif.: A 3 sq mi area is the first phase. Service is $8 a day or $16 a week; monthly prices weren't noted. In MetroFi's solo rollouts, an ad-supported free option is always available, along with a $20 per month ad-free version. Update: The press release didn't note it, but there's a 512 Kbps free ad-supported version, too.
AT&T has a bit of nonsense near the end of this press release. They claim the largest Wi-Fi network in the US, and "50,000 hot spots spanning 81 countries." Uh, right. First, the 10,000 hot spots in the AT&T WiFi (no hyphen) network include about 8,000 McDonald's, access for which is resold from Wayport to AT&T under terms that have never been disclosed. That leaves about 2,000 other locations, mostly dribs and drabs, and a few major airports inherited by Cingular from the former AT&T Wireless. Second, the "50,000" hotspots are all aggregated from other networks, and resold on a metered basis.
When T-Mobile claims to have the largest US network and a worldwide roaming partner network with metered rates, well, you can buy that. T-Mobile operators over 8,500 US locations, and is part of a worldwide alliance (including other parts of Deutsche Telekom) for metered roaming paid out of your US account.