Christmas in Vienna is almost like a live.Three Tenors album, only with Diana Ross taking the place of Luciano Pavarotti.That alone makes for quite a change, since Ross'style of singing is decidedly different from Pavarotti's,but she acquits herself well. Of course, it helps that she is supported by a wonderful assembly of musicians, from Jose Carreras and Placido Domingo to producer Michel Glotz and arrangers Lalo Schifrin and Antoni Parera Fons,all of whom help make the mix of contemporary carols,hymns, traditional carols and religious tunes an attractive holiday album.