IMHO In My Humble Opinion

I have argued in the past, that at least in the US, Google isn't technically invading privacy with Google Street View.

This is dependent on the assertion that "privacy" is defined by what the law says, which I will readily agree is a sort of silly assertion: clearly the generally accepted definition of "privacy" isn't really captured by our legal framework. (I believe that some online lawyers assert that storing information based on someone's IP address isn't necessarily "private" because IP addresses aren't guaranteed to be unique identifiers. Never mind that they sometimes are unique identifiers.)

Something that I've meant to imply in some of my earlier conversations about this issue is that if the law doesn't cover our conception of privacy, it's the law that ought to change (and then, hopefully, Google and other data providers will fall in line.) Solving the problem in the specific case of Google doesn't actually solve the problem: they're not the only perpetrator of these alleged privacy invasions, they're simply the highest profile.

I believe this posting of an open letter to Google about street view in Japan is probably the best presentation of this argument that I've seen. Rather than try to make some sort of argument based on privacy law, it's an appeal that Google is violating Japanese customs by making this information easily available. The letter's author says in a couple of places that maybe it's different in the US, but based on much of the press I've read, I think I disagree: it's also against American custom to make this information overly public. Perhaps it's not as deep of a custom, but given the gut reaction of some people who discover these images of their houses online, I'd hesitate to say the Japanese have a monopoly on outrage over Street View.