What is the difference between posting a picture of people on a public street on Google Street View or on Flickr?Obviously - the information is the same, only the information access is different. There's no difference in kind of information - just a qualitatively easier interface to getting it. Anyone can take a plane and a taxi and take a picture of my house - but I don't expect that anyone will bother. So it's jarring to find out suddenly that anyone with a DSL line and 30 sec to spare can get the same effect.
Our expectations of privacy (and privacy laws) are driven by what's easy, and what's likely, not what's theoretically possible.
My personal take on this - it's another great example of how smoothly information can be integrated together, when it's all grounded in the physical world. Entries from maps + business listings + satimages + street view are relatively easy to search together and visualize simultaneously, since they're all tied together by physical location in space.