Scribd managed to get 9 front-page links on Digg, and a couple on Reddit, in the last month. That is why their traffic is up so fast. Personally, I assumed that the Scribd guys were posting these high-traffic pages themselves in order to get noticed by diggers and redditers.

Every scribd page that I looked at (from Reddit and Digg) could have been done just as well (and in some cases, substantially better) as HTML, using any blogging software (e.g. WordPress, blogger.com) instead of Scribd. The value-added features it offers (basically, a worse-is-better reimplementation of Adobe Acrobat, and collaborative editing) only caused me discomfort.