For new cocos2d users on Twitter, the toughest thing to figure out is who to follow. If may be helpful, here is my list of cocos2d and game developers on Twitter that rose to the top:
1. Ricardo Quesada
Key contributor to the open-source cocos2d for iPhone project
Twitter Handle: @cocos2d
2. Steffen Itterheim
Author of Learn iPhone and iPad Cocos2D Game Development (Apress). Currently working on Kobold2D, an improved Cocos2D.
Twitter Handle: @gaminghorror
3. Ray Wenderlich
Author of the most popular iOS/cocos2d tutorials
Twitter Handle: @rwenderlich
4. Rod Strougo
Author of cocos2d book.
Twitter Handle: @rodstrougo
5. Stepan Generalov
iTraceur game developer
Twitter Handle: @parkourDev
6. Martijn Thorig
Indie developer and owner of Small Gaming. Made Dropping and Terror and War.
Twitter Handle: @SmallGaming
7. Chris Wilson
Indie developer, creator of Super Turbo Action Pig
Twitter Handle: @abitofcode
8. Herman Jakobi
Founder of MinimaxGames
Twitter Handle: @hermanjakobi
9. Bogdan Vladu
Creator of LevelHelper and SpriteHelper, the popular tools for Cocos2d
Twitter Handle: @vladubogdan
10. Marco Neumann
Media composer, software developer, photographer, digital artist.
Twitter Handle: @marcotronic