I run a Twitter account successfully, I go to Twitter meetings and network, I think the tool is a great addition providing you run it correctly.
With followers and following, forget all that jazz, follow those who are of interest to you and naturally people will follow you providing you are talking something interesting and useful, never self promote on Twitter, this will get you nowhere and only lose you followers.
I have 3,026 followers, mainly these are SEO buddies, people in Spain and Scoliosis members which I know across various groups and pages I run.
What you need to get on Twitter are RTs (Re-Tweets), if you are micro blogging interesting articles, information, funnies etc then people will RT your message which will bring more attention to your twitter name and gain you more followers naturally.
Hope that helps