Facebook – Online Privacy from the Facebook ticker while playing games

Check (and keep checking) the privacy settings on your account.

On this page: http://www.facebook.com/settings/?tab=privacy

Make sure that you only allow friends to see your data.

On this page: http://www.facebook.com/settings/?tab=privacy&section=apps

There's a "Public search" option - make sure that's set to disallow.

There's a option for "Information accessible through your friends" make sure that you clear all the check boxes on that dialog.

There's an "Instant personalisation" page - not available for all users as yet - but when it does become available make sure you clear that option too.

On this page: http://www.facebook.com/editaccount.php?ads

There are options for Facebook ads to use your data - clear both options.

You have to keep checking because Facebook regularly change the options and the defaults are to be more open than you would like.

Ultimately you are joining a site whose premise is the sharing of information. If you're not happy about sharing something - don't post it to the site, either directly or as a link. If you're not happy about sharing anything - then don't sign up!

The Twitter updates go to your wall at the default level of privacy for wall posts. I think the people who created the Twitter app are responsible for adding the granularity for the privacy.

However, it doesn't matter, because the Twitter app cannot read your Twitter updates and repost them to Facebook unless your Twitter posts are public in the first place - public as in anyone can see them.