] Free tagging could help Web search in a couple of ways.
] If Yahoo or Google could enlist people to annotate
] visited Web pages or those which crop up in search
] results, it could be a valuable voter's guide for them to
] deliver better results next time.

Imagine. A site where people write commentary and annotation of
the sites they come across. For free. Propagating memes.
How unlikely.

] A key byproduct of free tagging for search would be a
] visitor loyalty coveted by all the providers. As many
] researchers point out, the cost to switch search engines
] is nothing, compared with instant messaging technologies,
] e-mail, or applications that carry what's called "the
] network effect."