I gave it a try and I thought it could be interesting for others. For example here is the Word Cloud for the Proceedings of TDWG 2008. Basically I just copied all the text from the PDF and gave it to Wordle for analyzing.
Click on the image to view it in their Java applet.
Then I did the same but with Markus post about TDWG 2008. And here is the result:
They look similar but Markus I think has a higher geek level :D
Finally I could not resist and checked how it would look this blog and here it is:
Seems that the words that use most are Google and Data, even more than biodiversity itself (10 counts for Google and 6 for biodiversity).
Finally, if you are interested in displaying word clouds in maps there is a recent post for one of my favorites blogs, cartogrammar. I dont see much use on it apart of that they look nice, and they indeed look nice!.