What does it mean? It means that every time you update your Geekzone Status using the "What are you doing?" box on the top of every Geekzone page this status will automatically be replicated to your Twitter stream:

Every time you update your Twitter from any other source (Twitter pages, ping.fm, Twitter clients), your status will be automatically replicated to Geekzone and shown in your public profile page on Geekzone. You will also see the updates in the Geekzone front page while you are login.
You know someone posted from Twitter when the blue "T" shows up in your stream, and someone posted from Geekzone when the yellow speaker shows up:

To allow Geekzone to post to Twitter on your behalf you need to update your Geekzone User Profile. First enable "Geekzone Status Updates" (A). Then you have to enter your Twitter Id and Twitter Password (B). You can check or uncheck the appropriate box to enable or disable this feature, but you will need to have the "Enable my status updates" option checked too:
So, who can see these updates? All your Geekzone Friends can see your updates in their own public profile pages. Also if you keep your public profile open then everyone visiting your page can see those updates. If you prefer to make it private so that only your Geekzone Friends can see it then just check the box to make it private (C).
What are the limitations? We don't show @ replies. The service just allows you to post to Twitter from Geekzone, and vice-versa. Also it may take up to 20 seconds for a message from one side to show up on the other side.
Also there's a "Geekzone Twibe" and you can join in now.
Big thanks to Phil at RedJungle (@redjungle on Twitter) for implementing the service for us.