List of official Google accounts on Twitter :

Google – Google’s main account on Twitter.

YouTube – For YouTube lovers.

Googleimages – For Google Image Search updates.

Googlereader – For news regarding Google Reader.

Googleapps – For latest and popular Google Apps.

App_engine – For Technical Updates on Application Engine.

Blogger – Acts like Blogger FAQS.

Googlewmc – Twitter account for Google Webmaster Central (main account)

Adwordshelper – main AdWords support account

Mattcutts – Matt Cutts, head of web spam team in Google

Are we missing any? Leave a comment!