Official Google blog says the following : http://twitter.com/Google - our central account http://twitter.com/Blogger - for Blogger fans http://twitter.com/GoogleCalendar - user tips & updates http://twitter.com/GoogleImages - news, tips, tricks on our visual image search http://twitter.com/GoogleNews - latest headlines via Google News http://twitter.com/GoogleReader - from our feed reader team http://twitter.com/iGoogle - news & notes from Google's personalized homepage http://twitter.com/GoogleStudents - news of interest to students using Google http://twitter.com/YouTube - for YouTube fans http://twitter.com/YouTubeES - en Espanol http://twitter.com/GoogleAtWork - solutions for IT and workplace productivity Geo-related http://twitter.com/SketchUp - Google SketchUp news http://twitter.com/3DWH - SketchUp's 3D Warehouse http://twitter.com/Modelyourtown - 3D modeling to build your favorite places http://twitter.com/EarthOutreach - Earth & Maps tools for nonprofits & orgs http://twitter.com/GoogleMaps - uses, tips, mashups http://twitter.com/GoogleSkyMap -Android app for the night sky Ads-related http://twitter.com/AdSense - for online publishers http://twitter.com/AdWordsHelper - looking out for AdWords questions and tech issues http://twitter.com/AdWordsProSarah - Google Guide for AdWords Help Forum http://twitter.com/GoogleAnalytics - insights for website effectiveness http://twitter.com/GoogleAdBuilder - re building display ads http://twitter.com/GoogleRetail - for retail advertisers http://twitter.com/TechnologyUK - for U.K. tech advertisers http://twitter.com/InsideAdWordsDE - for German AdWords customers http://twitter.com/GoogleAgencyDE - for German ad agencies http://twitter.com/AdSensePT - info for Portuguese-language publishers http://twitter.com/AdWordsRussia - AdWords news & tips in Russian http://twitter.com/DentroDeAdWords - Spanish updates from the Inside AdWords blog http://twitter.com/AdWordsAPI - AdWords API tips Developer & technical http://twitter.com/GoogleResearch - from our research scientists http://twitter.com/GoogleWMC - Google Webmaster Central http://twitter.com/GoogleCode - latest updates for Google developer products http://twitter.com/GoogleData - Data APIs provide a standard protocol for reading and writing web data http://twitter.com/app_engine - web apps run on Google infrastructure http://twitter.com/DataLiberation - our initiative for complete import/export of all data http://twitter.com/GoogleMapsAPI - about using Google Maps embedded in websites http://twitter.com/GoogleIO - Google's largest annual developer event Culture, People http://twitter.com/googletalks - notes from our @Google speaker series http://twitter.com/googlejobs - the voice of Google recruiters Country or Region http://twitter.com/googlearabia - news from the Google Arabia Blog* http://twitter.com/googledownunder - Google activities in Australia & New Zealand http://twitter.com/GoogleDE - Google in Germany http://twitter.com/GoogleKorea - News & notes in Korean* http://twitter.com/GoogleLatAm - Latin America (en Espanol) http://twitter.com/GooglePolicyIt - Notes on Google policy issues in Italy