If you have limited number of tags then its good to have cloudtags so tags page will have more importance and so it ranks good in search engine.
Personally I doubt it's importance any more. Previously it was a good way to automatically get main keywords on every page, automatically in bold for the more important ones. These days on page factors carry so little weight, that I doubt the difference would be noticeable. I added one to a site about a week ago and it hasn't made any difference whatsoever.
I think tag clouds are good for SEO, it depends on the keywords we add. However, tag clouds don't affect the way you optimize your site, and your blog.
If you think indexing the same content over and over under different URLs is "good" for SEO then have at it. Personally, I think tag clouds are terrible for SEO. Blogs already create tons of duplicate content with just category, archives, and posts... Tags just make it exponentially worse. But they can be good for usability. I NOINDEX all archives and tags pages, use custom excerpts, and only assign a post to a single category. EVERY page that gets indexed is unique as a result. Even the category pages have unique content since they are composed of only custom excerpts that appear no where else on the site (once the posts have rolled off the home page).
To get the most of your internal page popularity do not put tag clouds. But if you put nofollow tags to these link I believe it is okay.
Tag clouds are important for SEO.Make use of this in your SEO work.Keywords are used inside the tags.
search engine not consider only tag cloud, it will look back links also. Anyway we can use tag cloud as careful.
Tag cloud may be important if the keyword used in it are valuable and limited in numbers. Generally the total number of links on a page should be limited to 100.
Tag clouds are not good for seo, because it creates duplicated content on your site. Tag clouds can be useful for your visitors and can increase page views. And that may increase your income from, say, adsense. If you are using tag clouds on your website it's better to close tag pages from indexing.
Not much of a use the way I see it for SEO... However, if you are going with user friendliness, sometimes tag clouds can help
Tag cloud is good as an additional enhancement to SEO. Expecting magic from tag cloud isn't practical. If you properly limit the number of tag clouds and use then well, then it'll surely compliment the SEO campaign.
Yes TAG cloud is for improve internal linking of the pages. It is ofcourse very good for SEO. Tag cloud may be important if the keyword used in it are valuable and limited in numbers. Generally the total number of links on a page should be limited to 100.
There may be some argument nowadays that lumping a 100 keywords into a tag cloud is irrelevant - search engines nowadays understand much more about context.