Some people use only tagging – they create big clouds of tags and attach those to their posts. It is a common practice, but it looks ugly on wordpress.com blogs where (categories == tags) – since a popular tagging behaviour is to add multiple tags to a post, and to be inventive with tags names they end up with a large list of categories/tags in their sidebars. That’s noise.
Others use a small number of categories, possibly organized in a hierarchy (e.g., see categories on a sidebar of CaptSolo Weblog on the Semantic Web). That results in better categorisation of posts, but if (categories == tags) then you loose in visibility on sites such as Technorati because you will have a small number of categories per posts, and possibly those will be named in a way that’s meaningful to you but maybe not so much in demand overall.
More inventive people use both – have categories to “file” posts so they can group and find them, and have tags to attach more context to them and help people find these posts via blog/tag search engines.
But how can we make use of that for wordpress.com blogs? I want to have a small set of categories for my posts an a larger set of tags attached to those posts. Let’s try it.
Update: It worked! No reason why wouldn’t it unless wordpress stripped rel=”tag” from hyperlinks. Now this post has got one category “Information Management” and a couple of additional tags.