Improvements to processing for detection of site quality.
That's borderline link building related
I don't think its borderline martini - I think it is completely related.
Most of the updates in this realm, and Panda realm, are geared at understanding site quality.
Inbound links are a reflection of site quality and particular types of links that do not fit into the natural scope of quality, sticky, socially strong sites may be considered unnatural, non-editorial.
Lots of sites have survived the last update, and lots have not. I spoke to a friend recently who received the "dreaded" unnatural links message from Google. When I looked over his back links I seen a wide range of low quality junk links - the kind that has been helping spam sites develop nicely in Google SERPs over the years.
What is interesting is that in the message they referred to duplicated content links that were pointing from a number of article directories. The "inference" was that article directories are not editorial and natural, they are still forced links.
I think better interpretation of anchor text, utilizing anchor text to form a better understanding of signals and what is natural, and a drop of some anchor text signals are what many SEO's will ultimately remember 2012 for once all is said and done.