Wired.com has a good overview of what it believes is the death knell of the dedicated GPS industry: iOS 6 with 3D maps from Apple and whatever it is that Google will release in response.
I think the Wired assessment is true: dedicated GPS devices are dead for the mass market.
How many jobs will be lost?
How much wealth will be created as other companies flourish and individual consumers save hundreds of dollars by not having to buy separate devices?
Creative destruction; a brave new world; These are great things. The future will be awesome.