Tagging or social bookmarking ( a way of keeping track of all the websites you and community members like you use ) is becoming more and more relevant to helping web searchers keep track of their favorite sites. It's also starting to become a contributing factor in helping you get better search engine rankings.
Zeal announced a month or so ago about shutting up shop and you now find on their site a link to LookSmarts http://www.furl.net/ ( a new tagging, social bookmarking type site; such as del.icio.us ) This will probably end up being a good site for such activities, but you think Zeal could have done a better job in turning their focus.
Most online are not taking part of tagging, so the good news for you is that you can get into it, and started on it while the getting is good. Most SEO's are using this to help clients (and themselves) achieve better rankings by keeping track of the websites, articles and blogs that mean the most to them. They give the website, article or blog a "tag" or a keyword that is associated with it so you can find a community of people interested in the same thing. You might see on a blog where it says del.icio.us this or something like that. Well this is how you can keep better track of the things you like.
I am giving you the chance to really get into it now, so make sure if you are a small business owner online, or if you have someone doing the SEO for you ... make sure this is a part of the marketing! I am going to point out the obvious but if you really get into this .... its a great form of link building and increasing your link popularity!