Hi Patrick - haven't forgotten about you With a tag cloud there is a possibility of a dupe content penalty. They are useful for site usability but won't help for SEO. If you do use them, make sure you use the canonical meta tag.
Tag clouds can help both users and search engines to find content in a web site. However, it is advisable that you should put noindex on tags pages to avoid duplicate content penalty.
tag clouds can be helpful for you depending on your site. however the answer is not as simple as yes or no. how many pages make up your site? do you have many deep pages that google would otherwise not find without a tag cloud? these are some of the things you should be asking yourself to find out if a tag cloud will be useful to your site.