The speed and cost is partially technology and partially who's competing in your neighborhood.

Prior to Google's arrival, we had AT&T and Time Warner as choices...both super-expensive and low speed. 6-10 Mb/s would cost you $50-80/mo. We get better than that off of the local cell tower.

Then Google started digging in our 'hood, and suddenly AT&T started offering 200 Mb/s for $70/mo. Time Warner went low-cost: $24.99 for 30 Mb/s. (We added TW at this point.) This was almost a year ago.

TW and AT&T did no visible work in our neighborhood: the new speeds and plans were delivered over their existing wires. (Whether they upgraded hardware nearby, I have no idea.)

Finally, in January, Google finished wiring to our house, and we dumped TW. In part because the service required a modem reboot every day and in part because what we were really getting on wireless devices in the house was much lower. Now we're at $70/mo. and we get right at a gig to the wired connection and around 400 Mb/s to wireless devices.

For now, and probably for a few years to come, we will consider that "fast" and not *too* expensive.