I'd check into the a/an issue (<a href="http://i.imgur.com/ZT7Nf57.png" rel="nofollow">http://i.imgur.com/ZT7Nf57.png</a>), at least for the default/example phrase. Pretty funny though!
It's a neat tool but I wish it could better parse paragraphs and commas. I also had a few responses with the same curse words three or four times in a block of text making it a fucking boring read.
Pretty neat. From solely using that the prepopulated example input, my main gripe would be that it doesn't get a/an correct in the "cursed up" version of the sentence.
I was thinking it would be more like readability, but instead of reformatting the html, inserting curse words. How much more fun would cnn.com be?! But a good start!