An incredibly revealing post on some theories about Google's changes over the past 12 months was first noted by TW. However, the quantity and quality of information presented by Michael Martinez in his post at Spider Food is deserving of a closer examination.

...That Google is influenced by smaller content pages than it is by larger content pages....

I actually think this is because Google is focusing on term weight and related term weight, rather than frequency or occurence.

Inbound links are not important for the new content on established sites, provided that those sites are internally well-linked.

This is very true - pages on established, globally popular sites need only the right internal anchor text or title to rank highly in Google's searches. This follows Google's pattern of 'trusted' and 'untrustworthy' sites. Martinez goes on to name this factor 'child inheritance'. This is a good theoretical post, and one worth reading, although the application or reality of his comments should certainly be taken with skepticism until you can prove it to yourself in the SERPs.