I live in a zero lot line house in Turtle Rock, on a ~8k sf lot, and it actually seems to provide a lot of privacy. The neighbor has no windows on our side. Makes the yard seem larger as well. The homes sit between the yards, essentially, so it provides a good amount of noise attenuation (more than a fence or wall). Moved from CDM where I could hear my neighbors showering, so I may have a skewed view of things.
I guess its not technically zero lot line - the line is about 2 feet from the wall of the house - but you have to go through your neighbor's yard to see your wall. You are at the mercy of your neighbor, but I hope given the area and pricing that the neighbors are respectful and courteous - mine have been!