Locations are definitely important. I hear that N. Dakota is the Saudi Arabia of wind yet there is only a single windmill there. They also have more electricity than they need and they have a lot of raptors which will cause the bird societies to get involved. We certainly don't want to be killing too many eagles and hawks.
The economics seems to work very well with the 1.7 cent PTC. As the technology continues to bring the prices down I would either expect wind to develop faster than the available money from the PTC or the PTC will have to start shrinking to less than 1.7 cents per kwhr.
You are right about the arguments against wind. They are starting to sound very contrived and come from people who have some other issues of their own to get over.
I have no idea where you are getting those numbers, but the last time I looked wind was pretty expensive about 6 cents per kwh, but the tax subsidies helped bring it down into the competitive price range. One of the things not well discussed is the amount of blade maintenance (i.e. cleaning) and other kinds of maintenance required. Depending upon tower height and design (read that trade offs between high initial cost versus high maintenance cost) maintanence at a wind farm can be surprisingly expensive. Unless of course you just run them till they fail as some developers have done. Everything I have seen does not indicate that wind is a "cheap source" of energy. It may be cost effective under certain high fuel cost or inflation assumptions and certain tax credit assumptions, but by itself it is not cheap, at least from what I have seen. The firm I am with has recently worked with some folks trying to come up with fairly priced land leases for windfarms, so I don't think my economics are too far off base from the projects I have been involved with in the past.