You'd be surprised. I'd suggest that you create a lot more variations on the current buttons, with different colors and shapes and sizes; websites like
http://hicksdesign.co.uk make use of these buttons--he uses custom ones, but the idea is that he has those buttons there at all. Also, many webmasters don't even know what services to use to check pagerank and are confused by the whole idea; they may not have tacky sites or be new to the game, but they might be new to PageRank and Google SEO; therefore, my suggestion is that you also put an explanation of PageRank up on your website, that being one of your target audiences.
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