JS_Harris - 9:13 am on Jan 22, 2008 (gmt 0)

Tag clouds work extremely well from a serp point of vue but I'm slapping a huge disclaimer on that statement.

The reason for the disclaimer is that they need to be used properly.

Consider them a second form of navigation. Most sites have categories with links to each category in a navigation bar, here are some pointers on using categories with tag clouds.

#1 - do not repeat a category name as a tag.
#2 - ensure that you re-use the same tag names over and over, don't create variants of the same word, this is to keep related posts together.
#3 - do not shove the tag cloud to the bottom of a sidebar, it needs to be displayed prominently, above the content if possible, this is due to rankings.
#4 - If you're up to coding this, and you should be, place a tag cloud on each category page and ensure that it only pulls tags from that category.
#5 - Ensure that all of the tag names compliment the category name, that is, make sure they all belong as sub sets to that category.
#6 - Keep the number of tags small, else plan on writing a ton of content each day to keep them all fresh.
#7 - resist placing any article under a tag it is not strictly related to, likewise don't place the article under more than two or three tags - one is ideal though often two or three apply.

Those will get you started, search engines actually love having content categorized. Social media sites have paved the way to ensure tags are going nowhere now, wordpress has included them too.