Normal
We have been on the Millennium for 6 cruises and found that the Rendez-vous lounge usually has ballroom type music - mainly fox trots, rumbas, swing, waltzes, cha chas. However the dance floor is small (there are only two dance floors on the M-class ships - the Rendez-vous which is outside the dining room and one in the lounge - the Cosmos on Millennium - which may have the party band play sometime during the evening and then is the DJ and disco). The Rendez-vous is very crowded between the two dinner seatings - so much so that you can't really do ballroom as most people just dance in place. But about the last couple of hours after late seating, the dance floor empties out and serious dancers take the floor.