I am not sure this works. Would be interested to know what others think. This blog has implemented the big font = popular folksonomy style as their navigation. In this case, big font equals lots of posts in that category. For some reason I though it meant most popular areas of the site. Immediately a problem - should the big font point to the most popular stuff, the biggest section, the longest posts, you get my point.
More on folksonomies, or social tagging, if you will.
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