Rihanna, Coldplay and legendary Beatles singer Paul McCartney have been added to the Grammys lineup, according to an announcement made Wednesday, and will perform at the ceremony, sceduled for Februay 12th at the Staples Center in Los Angeles.  Rihanna is nominated in four categories, including Album of the Year, while Colplay earned a total of three nominations.  McCartney's performance at the awards show will come less than a week after the release of "Kisses On the Bottom," his latest studio album that is due in stores February 7th.