Me? Thus far - Canon -> Nikon and thinking about going back -> Canon
I know this thread has seen its day - but the level of difference you'd feel is minimal - if any - in your final images. I have shot Canon for 20 years - and due to a number of circumstances, I recently switched.. $40k worth of kit. Not something I'd suggest for anyone to undertake - whether it be $1500 or $40k - its a matter of the fact, that for many - this isn't something that is required. I switched due to the Canon bodies I was looking at would actually inhibit my ability to get certain shots, with the 1D & 1Ds Mk III focal issues. Apart from that - the switch TO Nikon would have been ludicrous, and not offered any benefit.
The "conversion of cost" either way for ANY other reason is prohibitively expensive; and doesn't normally mean you can get better pics. Yes before the D3/D700 came along - (to a lesser extent the D300) the noise difference was marked so a conversion to Canon would at times mean you could get a shot in low light conditions that you would be hard presses to get with the "same" lens in a Nikon. On the flipside BUT there are plenty of photographers who worked with the D100/D200/D2x etc and got amazing images in less than ideal lighting.
Nikon has stepped up with the D3/D700 and the glass. The glass is amazing - with the 24-70mm being my favorite lens, and SUPER sharp. The 14-24mm is great. With the current line-up - inclusive of the 70-200mm there is no reason you need to switch TO Canon. I'd hazard a guess that the D700x will have bot 24mp and 1080p video - if that's important to you. It will then blow the 5D2 out of the water, as the pro level focus of the D3/D3x/D700/D300 is nothing short of magic. Shoot these puppies using AF-ON in continuous
mode and it is a magical experience as they lock in amazingly low lighting conditions.
Its about the you as the photographer and how you see. IF the switch will make you see differently - even if its your own self-perception that then change your confidence or change how you see - then it may well be worth it.
The D700 is really an amazing camera - with the fuller pro-body experience. I find changing shutter speed and aperture in manual
mode faster than on my previous Canon gear with the command dials being in the exact position they need to be.
I know you've mentioned you are decided to stick with Nikon - so its moot in a way - but if you grab a D300 and/or D700 they are FAR more solid and pro than the Canon equivalent.
Yes - and now I face the facts that as my main assistant doesn't like the D700 - and I shoot with a bunch of other Canon shooters as second shooters and assistants - I may need to switch at least SOME if not ALL of my gear back....
Sigh..