Yes it is a shame Nikon don't make a mirrorless camera as serious as the D800.
They have very old school people who think optical viewfinders and mirrors are somehow relevant in 2013.
Of course from a business perspective swapping to mirrorless may involve an entire lens line-up to be wiped from shop shelves. Canon and Nikon both got bitten in the ass big time when they moved from the old AI / FD glass to modern Nikon and EF lenses so they are relucant to let this happen with the mirrorless revolution. Both pay lip service to the mirrorless models, the lens line-ups for the EOS-M and 1 Series are PITIFUL.
I think they want us to keep buying the old glass and not just to adapt any old crap to their new camera 
But Sony have gone the other way since they don't have such a big legacy of existing glass to protect. They actively promote third party lens adapters in their Sony Style stores, at least here at the flagship one in Berlin. Interesting strategy which I feel benefits their camera sales, but not so much their E-mount lens sales. So you can understand Nikon and Canon wanting to hold onto their magic ability to 'lock' people into a specific lens range.