I tend to agree with the author, and I find tag clouds too cluttered. Some might argue that it's a good way to see what the web site/blog is about, but sure there must be a better way to do that. If my blog is mostly about, say, technology then you can easily see that from the blog name, tag line, or the titles of the top two posts. I cannot see why tag clouds got so popular!!! Am I missing something?
If you find what you're missing, please tell me. I really don't get it either. It's a list of common keywords arranged in a magic cloud with visual intensity feedback. It's good for a quick overview of what the site is about.
But I think the title and tagline of a blog is a better indication. A tag cloud is just a visual cacophony of symbols my mind tries to parse unsuccessfully. If I'm on a blog I haven't been to before it's generally because I came from here or google. In that case, I'm there for a specific keyword or reason already.
The big thing that really bugs me about tag clouds is when I click on one and it leads me to another. That's just not helpful.
'... if my blog is mostly about, say, technology then you can easily see that from the blog name, tag line, or the titles of the top two posts. ...'
One thing in favour of tag-clouds I've found is they are finer grained. If the knowledge domain is 'foo' you can quickly work out how the vocab is skewed to a particular subject. This is useful, unless they are spammed.
'... is it worth the noise it adds to the site? ...'
On the front page, maybe not. I tend to use the maps less regularly than every day. I check the entire vocab, not just the big words (though they do stick out). You're making a fair point though. I had the same beef with the ruby on rails image maps where they take up space & are indecipherable (to me anyway).
It's a visualization. It's good for certain things. It's bad for others. I have seen tag clouds used very well, for example here:
http://chir.ag/phernalia/preztags/