> I would say that a book musical (Oklahoma, The Sound of
> Music) is the old-style standard.
> ...
> Plays like Joseph and the Amazing Technicolor Dreamcoat
> have virtually no spoken dialogue - almost everything is
> sung. That is becoming the new standard for musicals. ... These might be called operettas.
> ...

It's funny how perceptions change over time, and art moves in cycles. Fifty years ago, you'd have said the opposite. The operettas of the late 1800s, by folks such as Gilbert and Sullivan, were the old style, and book musicals were new. In between, it was about straight stories broken up by unrelated song performances. So I wonder if that's what we're headed to once we realize that Andrew Lloyd Webber isn't all that hot after all.