Regarding the question for L.A. Ratings:
Los Angeles is a mixed bag. Personally I would expect better being a major entertainment center, studio town...etc.
On a 1 - 10 Scale
CBS - (8-9) Most consistant
KNBC - (6) Intermittantly loses HD and 5.1.
KTLA/WB - (5-6) Intermittant loss of HD and out of sync audio....also, two big bright disgusting logos.
KABC - (8) 720P looks great on my set...siganl a bit weak, occasional breakups or loss of HD....but rare.
KCAL - No HD
KTTV/FOX - (7) The engineers seem to be on the ball and they finally got one small logo in the corner. FOX shows though often don't have great pix quality.
KCOP/UPN (0) No HD
KCET/PBS - (4) Muticast causes awful motion pixelization and no 5.1 audio. They also have screen clutter with the big national PBS logo upper left and KCET's big logo, bottom right.
Edit - Re KTLA: I'm watching the Wed. 2/2 primetime shows and they are HD and I don't see the motion pixelization that has plagued their broadcasts. New gear? They were off the air yesterday (2/3)...not sure what's going on over there.