My mother will never organize her web pages with tags.See also today's post on the Dead 2.0 blog, "Ask Skeptic's Mom: What's Tagging?"
What's missing from the tagging world is automatic learning. People shouldn't have to find the 'save' button, click it, fill in tags, and hit save. My browser history says a lot about what interests me. The time I spend on a page says a lot about what I value. Any social activities I initiate or receive can inform a machine what the world around me thinks about.
The influencer is clearly willing to work harder ... but everyone else will need something more personal to happen as a result of tagging to warrant the amount of effort to do it.
See also my previous posts, "Manual vs. automated tagging" and "Social software is too much work".