Nigel,
It sounds crazy, but, with MAN having 7 confirmed new long haul routes, 1 more almost confirmed in the wings, increases on 5 others including Etihad almost doubling capacity, you can be certain Emirates are far from finished at MAN.
4 daily is no surprise, its been hinted by Emirates before, and Im lead to believe the Milan-JFK route was very close to being routed through MAN anyway, Milan just pipped us to the post.