Will this reduce my bill and improve services?
Or will the companies just pocket the difference and do nothing?
One thing ATT could do is improve their 3G reception (just improve on their existing coverage rather than sparsely expand into new ones)
Probably won't do much to reduce your bill. The credits are there to help the carriers improve coverage. So it might improve service if the carriers determine that they need to do so in your area.
It sounds like they will only receive this credit if they build out rural areas... like here in MI that would be considered "up north". They have wireless internet up north, but it's really not that good and not that fast. Bleh!
Does it matter? If you pay taxes, you're paying for it, anyway.