The D700 is definitely not all that which I have been reading from posts. The only thing it has on the Mk2 is the 5FPS. Think about the 51 pt AF for a sec. Overkill in some respects. The only ones I think are worth while are the 15 cross types. The rest are cool but only for the sports aspect. The Mk2 has it's 15 cross types of which 9 are selectable and 6 assists. The 3.9fps to 5fps...I'd much rather take the 3.9fps with almost twice the resolution!! If I really need a 12mp 5fps camera I'd keep my 40D or get a 1D Mk3 (granted they are not full frame!! I understand that point). Look at the ISO specs. D700 - 200 to 6400 w/ 100@L, 12800@H1, and 25600@H2; 5DMk2 - 100 to 12800 w/ 50@L and 25600@H1. I again lean for the lower option for cleaner pics and can still get the 25600 that the D700 can get. Actually I think the D700 having the 100 as a low setting is a ploy just to say that they can reach the 25600 mark raising the entire bracket a stop to do it (just an opinion). The VF's, D700 95%, 5Dmk2 98%. The D700 being able to use all the lens format is a plus to it with no Ef-s use for the 5DMk2. But who really cares about that?? The D700 seams to have better sealing, the 5DMk2....it's a Canon!! Better IQ, uses the lenses I have, better layout and ergs, and if it's ANYTHING compared to the original 5D IQ (esp Hi ISO quality) then it's going to be friggin awesome!!.
It's all personal opinion of course, but I just don't see the D700 as good as everyone thinks. If it was 16Mp or higher then Nikon would have hit it out of the park with those features. D700 or 5DMk2?? What do you want to sacrifice, IQ or features? My choice..5D Mk2 and either a 40D/50D or 1D Mk3 as a secondary when I need the speed.
Of course I can't afford anything with current gas and food prices until my kids move out but it's a goal. You Nikon users are getting good gear options now though. I must admit that.....
EDIT - after taking so long to post I have read the new posts just above me. The D700 has the MUCH better spot metering also!! And I can't comment but have heard Nikon's flash system is head over heals compared to Canon's. I still don't use many flash features on my 580EX and studio lights so I just can't say.