I guess you didn't miss the big hype about Googles OpenSocial (link doesn't work so far), which is a set of open API standards for social networks. I like Google for using open standards and working with and not against the community. But regarding this opening of social networks (same for FOAF/XFN) I have strong concerns as we lose too much control about the data and our privacy. Ralf Bendrath and others precisely describe the problems.
The Internet is challenging our current understanding of privacy/identity/society. Maybe we just have to accept this change and must adept our attitudes. For me personally it is not a problem that a potential employer can find out that I have fun in my spare time (as long as the information is correct ... which I cannot control) for other it might be different. But the potential abuse of this easy-to-harvest data by governmental agencies makes me refuse to stop questioning the legitimation of these technologies.