Taken to its logical conclusion, the multivocal approach would open public museum exhibits on for example genocide and natural history to accommodate the views of neo-nazi revisionists and creationists. This thankfully isn't happening. So multivocality is not such a big deal after all: political correctness rules the museums.
I published an essay in Swedish on this subject in Folkvett 2005:3, and it's also available here.
[More blog entries about museums, multivocal, relativism, Sweden; museer, mångstämmighet, relativism.]