This page should have all the blog posts I wrote as a Googler on the Google Webmaster Central Blog. This page is here so that I can find these quickly when I'm asked about a question a post helps answer.
Making websites mobile-friendly (Feb 2011).
Recommendations for building smartphone-optimized websites (June 2012). Be sure to also read the recommendations themselves.
Giving tablets the full-sized web (Nov 2012).
Changes in rankings of smartphone search results (June 2013).
Making smartphone sites load fast (Aug 2013).
Smartphone crawl errors in Webmaster Tools (December 2013).
Crawling and indexing of locale-adaptive pages (Jan 2015).
Update to Webmaster Tools search queries (Feb 2011).
Sharing advice from our London site clinic (Apr 2011).
Supporting rel="canonical" in HTTP headers (June 2011).
Raising awareness of cross-domain URL selection (Oct 2011).
Tips for hosting providers and webmasters (Dec 2011).
Better titles in search results (Jan 2012).
Rich snippets guidelines (Oct 2012).
Easier management of website verifications (Mar 2013).
Making site moves easier (Jun 2014).
Updating our technical Webmaster Guidelines (Oct 2014).