It looks like Google’s cracking down on crappy inbound and outbound links.
The sites that fit â€œno pages in Bigdaddyâ€? criteria were sites where our algorithms had very low trust in the inlinks or the outlinks of that site. Examples that might cause that include excessive reciprocal links, linking to spammy neighborhoods on the web, or link buying/selling. The Bigdaddy update is independent of our supplemental results, so when Bigdaddy didnâ€™t select pages from a site, that would expose more supplemental results for a site.