Telerama says it has 60 hotspots and 600 users: But it's not clear if those 600 users are monthly subscribers or if some of those have signed up for one time use. Of those customers, only four use PDAs to connect.
I think that an increase in PDA users would spur a major uptake of Wi-Fi in the mass market. Wi-Fi customers today are business users who have laptops. But if more people--not just business people--carried around lower cost PDAs, they might start using Wi-Fi for entertainment applications, like downloading music.
T-Mobile also has hot spots in Pittsburgh, some of them right next door to Telerama sites. Telerama is participating in Intel's free Wi-Fi day even though Intel isn't officially including Telerama in the day. Telerama hired college students to hang out in its hotspots and talk up the service for the day.