Regarding No-Follow links, the user asked whether inclusion of such links into websites can adversely affect SEO of the site. Matt gave a straight answer in its negation. He clarified that No-Follow links normally do not impact the rank of a site. However, over ambitious blog commenting can have an indirect effect. Users may complain against such strategy reporting them as spam, against which Google might take disciplinary actions. However, he did mention that actions are only taken in cases of large scale abuse on part of the webmaster.
Automatic page generation was the concerned involved in the second questions. The user referred to those scripts that automatically generate pages with only advertisements and the message describing lack of search result for the link clicked by the user. Such sites violate webmasters guidelines by Google and have worth for the search engine. He urged upon users to report against such sites and block such pages on theirs lest they be penalised.
The third SEO asked that how the effect of Panda can be found out. Matt said that relevant and comprehensive content that is independent of key word stuffing or any other short term practices is good enough to avoid getting affected by Panda. Consistency gained through proper structuring of sites and their contents is rather what ensures steady rise in web traffic.