Word clouds, when done well, can give you ata glance what's going through the minds of 100's, 1000's or even millions of users. If applied to just one persons writting then it probably just shows you that persons favourite words but when applied to user posts then it becomes a hand on the pulse of the web.
Obviously you'd want to just pull nouns and perhaps adjectives as it wouldn't look very interesting just seeing the word "and" in huge letters in the middle of your cloud. With minimal preprocessing they produce a reasonably accurate view of what people are talking about.
I think it would be very interesting to see what comes out when applied to the daily posts on a site like this.
Mike Mike Mike Mike
Mike Mike Mike Mike
Mike Mike Mike Mike
Mike Mike Mike Mike
