Questions to EV owners in the DFW region

Howdy, I am new to this forum . I am currently looking into the option to replace my gas guzzling car with a plug in hybrid. I have not decided on make and model yet since I just started looking. But I would like to get something which brings me back and fourth to work with running on battery only.
My questions are around the public charging stations, incentives and the energy provider here in the DFW area.

• Charging stations:
  I live in Plano and I have seen that there are lots of public charging stations around the area. From the recreational facilities of the city to stores like Kroger or Halfprice Books. How much does it cost to recharge a car at these stations? Are they charging per kw/h used? And how is billed? Per credit card?
  Also from what I have seen most of these charging stations have been provided by Blink/Ecotality which filed for chapter 11 in fall last year. Do they actually still work? And looks like there are some charging stations on private properties as well. Like at TI. Can they be used by non- employees as well?

• Incentives:
  I have seen that there are still government tax credits. Up to $7500 for a Chevy Volt. Are there any additional state funded incentives for new plug in hybrids?

• Electricity providers:
  Does it make sense to choose an electricity provider with lower rates at night? I am not sure these are even offered here in TX since most people have the most usage during daytime when the AC units are running at full blast. But the car will be charged at night.
  We have two AC units plus pool I wonder if the charge of the electric car actually makes a big difference compared to these kW guzzling units.

Thanks a lot
Stefan