I don't know if it's city wide or not, but you can probably get it in a lot of places. In NYC, they are turning all the city parks into free wi-fi areas but it isn't yet completed.
I think the one in Texas is wifi through the electrical lines. I know that here in Arizona, one of the major cities here (it escapes me which one... just not mine!!!) is offering it.
I know this is not the case in Europe, but in the US, broadband isn't available everywhere. Most of the rural areas here are still not wired for broadband. The way wireless is becoming so prevalent and getting so much better is probably really exciting for the people who can't get regular broadband right now.
I find it amazing how far behind the U.S. is on something. In the U.K., there was a law passed saying that people had to have broadband available to them by a given year ...and I think that is next year. Doesn't matter how remote you live, you get broadband.