You desperately want to attend Katy Perry's raucous San Antonio concert, but your kid sister has absolutely zero interest in tagging along, and the mere thought of going stag strikes fear into your heart. All seems lost, but worry not -- because Ticketmaster and Facebook have just joined forces to create a new feature that weds concert-going with social networking. As of today, users purchasing tickets to select events can easily find out whether any of their Facebook friends are also attending and where they're seated. All you have to do is connect to Ticketmaster with your Facebook account, find your concert of choice and use the interactive venue map to
