The biggest gathering of A-list rock acts this Grammy weekend in Los Angeles will not be Sunday at the Grammy Awards, but Friday night when many gather to pay tribute to Bruce Springsteen as the MusiCares Person of the Year. Among those on hand at the L.A. Convention Center will be Neil Young, Elton John, Jackson Browne, Patti Smith, Eddie Vedder, Sting, Mumford and Sons, Ben Harper and many others. Proceeds from the annual Person of the Year tribute provide essential support for MusiCares, which ensures that music people have a place to turn in times of financial, medical and personal need.