I’m on the train from London to Manchester in first class with a table and power socket, and a 3G dongle plugged in to my laptop. It’s pretty amazing that I can do this at all, but let’s just say we don’t have ubiquitous wireless data *yet*.
It works — just. A lot of the time, including any time we go through a tunnel, the data disappears completely. AJAX web apps don’t always behave very well when this happens. Google Mail and Reader at least display useful error messages. Facebook often gets stuck and no amount of refreshing or clicking stop has any effect. Google Gears and similar should improve matters.
Quite often I have a green light, meaning GPRS. This is almost the same as having no connection at all.
When I have a blue light, meaning 3G, everything is pretty good. A blue light might last 3 or 4 minutes at a time if I’m lucky.
Part of the problem is the transitions between states. If you only load half the web page and have a bit of a glitch between cell towers, the whole web page fails and there is no alternative but to start again.
Obviously better data coverage will help. But I think what would be really useful is an alternative to TCP that is designed to cope with internittent connections.
I am impatient to live in a Vernor Vinge novel!