WriteToDone has a post about How to Make Your Site go Viral on Twitter which is about using Twitter to build site traffic.
CopyBlogger writes about How Twitter Makes You A Better Writer. The 140 character limit in Twitter forces you to be creative.
Jenn Shallvey writes about Meaningful twitter.
More about Twitter:
The Inner Circles of 10 Geek Heroes on Twitter
The Ultimate Guide for Everything Twitter
