This wasn't an update, but it was an amazing revelation. Google CEO Eric Schmidt told Congress that Google made 516 updates in 2010. The real shocker? They tested over 13,000 updates.
To help fix crawl and duplication problems created by pagination, Google introduced the rel="next" and rel="prev" link attributes. Google also announced that they had improved automatic consolidation and canonicalization for "View All" pages.
After experimenting for a while, Google officially rolled out expanded site-links, most often for brand queries. At first, these were 12-packs, but Google appeared to limit the expanded site-links to 6 shortly after the roll-out.
Google rolled Panda out internationally, both for English-language queries globally and non-English queries except for Chinese, Japanese, and Korean. Google reported that this impacted 6-9% of queries in affected countries.
High-quality sites algorithm launched in additional languages (Google)
Google’s Panda Update Launches Internationally in Most Languages (SEL)
Webmaster chatter suggested that Google rolled out yet another update. It was unclear whether new factors were introduced, or this was simply an update to the Panda data and ranking factors.
Official: Google Panda 2.3 Update Is Live (SEL)
A Holistic Look at Panda with Vanessa Fox (Stone Temple)
After a number of social media failures, Google launched a serious attack on Facebook with Google+. Google+ revolved around circles for sharing content, and was tightly integrated into products like Gmail. Early adopters were quick to jump on board, and within 2 weeks Google+ reached 10M users.
Introducing the Google+ project: Real-life sharing, rethought for the web (Google)
Larry Page On Google+: Over 10 Million Users, 1 Billion Items Being Shared Per Day (TechCrunch)
Google continued to update Panda-impacted sites and data, and version 2.2 was officially acknowledged. Panda updates occurred separately from the main index and not in real-time, reminiscent of early Google Dance updates.
Official: Google Panda Update 2.2 Is Live (SEL)
Why Google Panda Is More A Ranking Factor Than Algorithm Update (SEL)
Google, Yahoo and Microsoft jointly announced support for a consolidated approach to structured data. They also created a number of new "schemas", in an apparent bid to move toward even richer search results.
Google, Bing & Yahoo Unite To Make Search Listings Richer Through Structured Data (SEL) What is Schema.org? (Schema.org)
Initially dubbed “Panda 3.0”, Google appeared to roll out yet another round of changes. These changes weren’t discussed in detail by Google and seemed to be relatively minor.
It’s Panda Update 2.1, Not Panda 3.0, Google Says (SEL)
Google Panda 3.0 (SERoundtable)
Google rolled out the Panda update to all English queries worldwide (not limited to English-speaking countries). New signals were also integrated, including data about sites users blocked via the SERPs directly or the Chrome browser.
High-quality sites algorithm goes global, incorporates user feedback (Google)
Panda 2.0: Google Rolls Out Panda Update Internationally & Incorporates Searcher Blocking Data (SEL)
Responding to competition by major social sites, including Facebook and Twitter, Google launched the +1 button (directly next to results links). Clicking [+1] allowed users to influence search results within their social circle, across both organic and paid results.
Recommendations when you want them (Google)
A major algorithm update hit sites hard, affecting up to 12% of search results (a number that came directly from Google). Panda seemed to crack down on thin content, content farms, sites with high ad-to-content ratios, and a number of other quality issues. Panda rolled out over at least a couple of months, hitting Europe in April 2011.
The 'Panda' That Hates Farms: A Q&A With Google's Top Search Engineers (Wired)
Google's Farmer/Panda Update: Analysis of Winners vs. Losers (SEOmoz)
In response to high-profile spam cases, Google rolled out an update to help better sort out content attribution and stop scrapers. According to Matt Cutts, this affected about 2% of queries. It was a clear precursor to the Panda updates.
Algorithm Change Launched (Matt Cutts)
Latest Google Algorithm change (Search News Central)
In a rare turn of events, a public outing of shady SEO practices by Overstock.com resulted in a very public Google penalty. JCPenney was hit with a penalty in February for similar bad behavior. Both situations represented a shift in Google's attitude and foreshadowed the Panda update.
