Im expecting a Cathay Style Business class, as in my opinion that is the closest to a Business/First class seat out there at the moment. All the Staggered seating in other Business Class's are nice but Cathay is the one to beat.
The width of the 787 is between the 777 and an A330 if im not mistaken so that should be interesting too see what they can do with that.
Since the lounge opened in London this route will definately be on the flagship route. However, from the current ANA configuration of the 787 that they used on the NRT-FRA route, the capacity of this aircraft is significantly lower than the current A346 and 777.