Grid parity means that the cost of electricity generated by Solar PV is equal to if not less than electricity generated by fossil and other "brown power" sources. I'm collecting here articles on it, including those claiming that grid parity has been reached in various areas of the world.
2/13: A New Mexico facility claims to be selling Solar-PV-generated electricity for less than coal-generated electricity. (Source).
10/12: A Spanish PV installation claims grid parity.
9/12: "Solar electricity is getting cheaper, and analysts predict that it will be as cheap as grid electricity by 2015 in half the countries of the world." (Source).
7/12: "Solar PV Close to 50c/Watt"
Claim: grid parity reached in Brazil.