After shooting some situations where I really could have used good hi iso, I'm re-jigging my systems. My p&s is fine (DLux4), and I have been using E-P1 for "higher quality street" with Pentax K20d and ltd primes for "more serious" stuff. I'm more on the art side of things, but do end up shooting for work on occasion, mostly documenting events and projects.
So last week I shot the K20d, 5Dmk2 and D700 back to back. I was impressed with all three (for different reasons), with the 5Dmk2 and D700 winning hi iso easily. The D700 ended up giving a bit more "crisp" files (shot tiff) but these were shop demo cameras and I didn't have time to tweak settings so I'm not sure how much to read into things. The 5Dmk2 felt better in my hand, but D700 was better built. D700 had some AF misbehavior - not sure if it was thrashed or settings.
So never one to hesitate much, I sold off a few of my Pentax FA ltd lenses and E-P1 kit with the plan of getting a FF setup and using the Pentax as a "high quality street," possibly switching to a K7 body with my remaining 43/1.9 and 50-135*. The GF1 and possible Leica lower end might push the Pentax out for the street thing, but I still want the FF.
So with no legacy glass, any advice? I'm starting from scratch. I had a Nikon D70 a few years back and did like the 105 micro, but that is long gone. There aren't any ltd prime equivalents in Canikon land as far as I can tell, but I'd likely get some hi quality zooms as they are much easier to use when I'm doing events, along with a few fast primes. Seems like Nikon is a bit pricier for equivalent glass at the moment.
This being the Canon board I figure the 5Dmk2 would get the nod, but the getdpi community is a lot more balanced than some other ones (to remain nameless) and many here seem to shoot different systems.