As I grew up in Los Angeles, not only did I recognize that it was L.A., I recognized that it was filmed at the street corner of Beverly and Rossmore in the Hancock Park section of L.A.
As I watch TV, I constantly recognize the geographically errors, but I try to take it one step further and try to get to the very specific location since I know L.A. so well.
On a related note, one guy that got the geography and the "look and feel" right was Jack Webb in his NBC Dragnet (1960's version) and especially Adam-12 police series. I have never lived in California, but I know the geography of Los Angeles well enough to find my way around, and even though Adam-12 is pretty dated, I still recognize some of the places where it was filmed.
Another series that did well in terms of geography (also on NBC) was Homicide: Life on the Streets, which was filmed in Baltimore and scripted to take place there. There was a crime scene involving a bowling ball being dropped onto a car (with fatal consequences), which very obviously was filmed on the freeway section of U.S. 40 (former I-170). And at least once or twice, the storyline involved I-95 or I-895, which was fun to see.
The various Dick Wolf Law and Order shows were and are pretty obviously filmed in New York City. Across the Hudson River, the outside scenes on HBO's Sopranos were almost without exception shot in New Jersey (anyone remember the great episode where Paulie and Christopher end up
lost in the Pine Barrens?).