I used to think that (mobile) phone numbers might play an important role in identity as they are quite stable for people. For instance, I have had my current number since 1999. But now I am wondering whether phone numbers will become meaningless entirely. I receive very few calls that I did not ask for on my mobile - most calls instead are pre-arranged via email. For any pre-arranged call, I could eventually use some form of IP telephony that will be namespace based (e.g., I already often do these kind of calls viae Skype).
That leaves people who need to reach me in an “emergency” — e.g., the kids’ school when one of them shows up at the school nurse. If I got a new phone number it wouldn’t be that hard to think about the half dozen places or soe that need to know about it. Ideally at some point in the future though I could simply tell the school to call me at “albertwenger.”
In a way phone numbers are IP addresses for people. If we had the web services equivalent of a gigantic telephone book (with some kind of permissioning) phone numbers would be pretty meaningless. That transition is, however, likely to take a very long time because we are missing the right standards. We need something like DNS and SMTP but aimed at the individual namespace and real-time communication. Paging DARPA?