Nathan Weinberg spots a tool named Search engine spam detector. The tool looks at a particular URL and classifies what elements on the page may raise a spam flag at a search engine. So let us test it out on the SEW Blog, shall we? :)
According to the tool, this site is completely spam free. The tool hasn't found any invisible text, the tool has not detected any unnatural text, the tool hasn't found any significant keyword stuffing tendency in HTML code, and the tool hasn't found any doorway farm.
So the SEW blog is more white hat when compared to SEroundtable.com, I got invisible text.