I made the same move, but from a D7000 DX rather than a D700 FX.
I bought a 5D MK3 and currently have a bunch of L glass and a couple of cheaper lenses:
16-35 F/2.8 II L, 70-200 F/2.8 II L, 50mm F/1.2 L, 40mm F/2.8 pancake, 50mm F/1.8 and I have just returned a 24mm F/1.4L II and a 35mm F/1.4L because I'll pickup a new 24-70 II in Japan next week.
I bought a Fuji X-Pro 1 for my wife in May and I've been using it every since
1) The Fuji is more Leica-esque. It's light, small unobtrusive and can give IQ to rival an M9.
2) There's nothing "better" about the Canon IQ, even though the system is FF and significantly more expensive.
This site has lots of reviews of the Fuji system from real world users:http://www.scoop.it/t/fuji-x-pro1
I would wait until the new Fuji firmware 2.0 is released on September 18th and read the reviews.
They have apparently fixed the sluggish auto focus problems.
You can start with a X-Pro 1 or the new XE-1 add the M mount adapter for $200 and start building up a system with Leica glass so that one day you can make the jump if that's where you want to end up.
I'm going to run both the Canon and the Fuji because they are different tools for different jobs.
I do a lot of street photography with the 18mm (27mm equivalent) and for this purpose, the Fuji is a better tool than the Canon.
The 40mm pancake lens is a particular favorite of mine on the 5D MK3...