Some thin affiliate sites, that are in competition with Google Adwords, have seen a drop in SERPs as a result. However, overall, the more successful affiliate sites, with enough content to avoid falling foul of Google Panda, have, if anything, seen improved SERPs including one of this writer's car insurance sites that has seen a climb in all of the more competitive keywords according to Google Webmaster Tools stats; so the argument that Google is bad for the competition is not the case where that competition offers good original content - a position that Google's Matt Cutts has always maintained.
Perhaps there's nothing terribly new about this - that 'content is king' is a well known central component of SEO. Panda just underlined it, though, with the effect that (human) content generators will need to work harder for Google to index new pages.
This writer has already found that Google has raised the bar on indexing content added to his websites. News items (because they have original content) appear to remain of greatest interest to Google on the sites he manages.
