Couple of points here.
First, with regard to "sections going supersonic so creating a shockwave", it might surprise you to learn that the supercritical airfoils used on the newer Airbus and the B-777 do just that, intentionally creating supersonic flow over the entire wing to "just move past" the high drag rise in the transonic region. Bit more complex than that, but I think that gives you the idea.
On the canard issue, I am a bit surprised that they are going that direction as well. I am curious to the advantages they found. The CG issues are fairly great for starters. It appears that the canard and wing in their design is not close-coupled, so the adverse effect of the canard creating downwash inboard and upwash outboard on the main wing would be minimized, but another aspect is that for high speed aircraft the thin aerfoils required on the canard could lead to a nasty leading edge stall. If this were to happen it could result in a rapid pitch rate change -- even possible to get an aircraft to tumble end over end as a result. Passengers take a dim view of this sort of antic.
The other advantages of canards would be positive lift from the horizontal stab, but this is really a non-issue in augmented stability aircraft, where we can have that situation in conventional design anyhow. The other operational advantage is eliminating pitch transients, but I don't think Boeing envisions the need for rapid pitch changes to avoid enemy fire in this aircraft!
So, I am curious about the choice of canards also.
[This message has been edited by Prof2MDA (edited 04 April 2001).]