Amex has recently unveiled previously unseen footage of Jay Z performing his Black Album cut “Public Service Announcement (Interlude)” during his gig at Carnegie Hall back in February. This further serves to whet apetites for his upcoming interactive concert at next weeks SXSW and, of course, for the UK based readers his ever approaching Watch The Throne tour. It has also recently been announced that the superstar will be headlining BBC Radio 1′s Hackney weekend. Excited is an understatement.