2009 Updates of Google

Real-time Search - December 2009

This time, real-time search was for real- Twitter feeds, Google News, newly indexed content, and a number of other sources were integrated into a real-time feed on some SERPs. Sources continued to expand over time, including social media.

Google Launches Real Time Search Results (SEL)

Caffeine (Preview) - August 2009

Google released a preview of a massive infrastructure change, designed to speed crawling, expand the index, and integrate indexation and ranking in nearly real-time. The timeline spanned months, with the final rollout starting in the US in early 2010 and lasting until the summer.

Google Caffeine: A Detailed Test of the New Google (Mashable)

Help test some next-generation infrastructure (Google)

Rel-canonical Tag - February 2009

Google, Microsoft, and Yahoo jointly announced support for the Canonical Tag, allowing webmasters to send canonicalization signals to search bots without impacting human visitors.

Learn about the Canonical Link Element in 5 minutes (MattCutts.com)

Canonical URL Tag - The Most Important Advancement in SEO Practices Since Sitemaps (SEOmoz)

Vince - February 2009

SEOs reported a major update that seemed to strongly favor big brands. Matt Cutts called VInce a "minor change", but others felt it had profound, long-term implications.

Big Brands - Google Brand Promotion: New Search Engine Rankings Place Heavy Emphasis on Branding (SEO Book)

Google's Vince Update Produces Big Brand Rankings; Google Calls It A Trust "Change" (SEL)