We're now in what could be called the Search 2.0 era--signaled by the rise of Google, Yahoo, and MSN, and similarly, the downfall of search forefathers such as Alta Vista, Excite, and Webcrawler. It parallels, with Web 2.0, this glorious age and hype machine.
First, a disclaimer: I hate the term Web 2.0. It reeks of dot-com geek elitism (as a Manhattanite, it takes an elitist to know an elitist), and it quickly runs the risk of making itself obsolete (there are already 654,000 results in Google for "Web 3.0," a term which has no meaning whatsoever). A Web 2.0 site can best be summed up as an online application incorporating at least two of the following features: streamlined design, community functionality, Ajax (a scripting technique allowing for dynamic interactivity, such as the smooth panning and zooming in Google Maps), and tags.

Tags are the most important part, for our purposes. Search marketers, at least those doing search engine optimization, were some of the first to grasp the importance of tags. Metatags, title tags, and their ilk were the core focus of Search 1.0. Now, with Web 2.0, tags are back, with a twist: instead of marketers and Web developers choosing them, the control has shifted to the consumers.

Consider, as a case study, Yahoo's My Web. Register there and you can save bookmarks, share them with others, and browse others' bookmarks (if they make them public). If you're a My Web user and you're logged in to Yahoo, searching on yahoo.com will bring up a Yahoo shortcut with a link to the My Web results for that query above the natural search results. Click that link and you're directed to the page of My Web links, with sponsored results along the side. This is just one example of users' tagged results landing high placement; be prepared to encounter more like it.

Here's a guide to some things you can do with tagging, and the site you should visit in each category.

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