WordPress Tag Cloud

Running a WP version 3 blog
My Tag Cloud is getting really big and means the footer is becoming too large
I know I can change the default limit on the number of tags I display

Is it best practice from an SEO perspective to use a different set of tags (say about 6) for every blog I write so they are a very close match to the content of every blog or be using a group of set tags for all blogs that I publish within a category?

If I do the first option then my Tag Cloud over time will increase to several hundred and then several thousand tags - Is this right?

Then I assume it will only display the first 30 in alphabetic order (or whatever I set as the default number) within my Tag Cloud in the footer of my website?

Or can I change this so in future it displays the top 30 most used tags across all my blogs? (which I assume would be more sensible)

Any help on this topic greatly appreciated

Cheers
Stu

Dump the tag-cloud. No one uses them, and Search Engines don’t really like them (see Matt Cutts’s video on the subject)

Proper categorization is a much better method (don’t have a big list of date archives either - useless).