In the market for a 77mm Polarizing Filter for my Sony A900 / CZ 16-35mm and CZ 24-70mm lens.
I shoot mostly now in Northern Arizona, I have been looking at the following filters:
Hoya 77mm (Moose) Warm Circular Polarizer Glass Filter
Singh-Ray LB Warming Polarizer
Sing-Ray LB Neutral Polarizer
Sony's CZ T* Polarizer.