Brutal. I live in city #2 (Provo, UT for those not keeping track), and, because I can't really help myself, all I can say is: this post brought to you via Google Fiber.
Originally, quite a bit of time was spent doing upgrades behind the scenes, then they switched everyone who was on the iProvo network to Google, then they started adding new customers in built-out neighborhoods. I am lucky enough to live in a neighborhood that they switched over relatively early. It looks like they've got quite a ways to go before they finish the built-out neighborhoods. There are a couple of places that people live that aren't built out, and those people will end up in the same end as you. Right now though? I see several Google Fiber branded vehicles a day.
For those at home wanting to know what it's like? Honestly, from a web-usage stand point it's about the same as the XFinity service we had before. When Google announced they were coming to town XFinity waved a magic wand and we went from sub-50, with highly inconsistent service to 100-plus with very good reliability. In the reliability department, Google is slightly better (it's only been a month, so we'll have to see about the long-run still). As far as the routers provided by both: the XFinity box had more options for power users and the Google box has all the power-user options (even simple stuff like staticly assigned DHCP) hidden fairly well. I'm not convinced the router is the best available, but my landlords don't want to swap it out.