I disagree with him. Professional looking web site is yet another step higher in delivery of "quality feel" your business may either project to customers or not.

I am inclined to think that craigslist, ebay an plentyoffish are rather exceptions. Every single one of them has very significant reasons to explain their success. So significant that design got irrelevant.

Certainly there is more to succes than a pretty looking HTML/CSS, but saying that ugliness sells is just wrong.