posted this on Jan 18 09:44 am
Your "Listed" number is the number of lists your Twitter handle is part of.
Lists are typically created by Twitter users in order to group certain topics together without having to actually follow the specific users. These topics can then be viewed at a users discretion in a separate stream, instead of in the users main feed where tweets are constantly displayed and updated.
For example, a user can create a list around "Technology News" or "Shopping" and only view the stream of Tweets when he or she is interested on reading up on just Tech or perusing their favorite brands.