Has just played with this. It's interesting!
http://timc.idv.tw/wordcloud/en/# via Jimmy Yen's Blog (in Traditinal Chinese).
Just choose RSS feed or Blogger name from the left column, enter the site feed path or the site name and then Start, e.g.:-
http://timc.idv.tw/wordcloud/en/#feed:http://ricehigh.blogspot.com/feeds/posts/default
Nice~! The analysis is accurate! The word Pentax shows up at the centre and the words K-5 and K-r also appear in larger words! :-)