Interesting one George,
I guess the need to make a fine art model that would be around 15Mp. The new high speed cameras are geared toward journalist and event photographers it seems to me. You are right (well I guess you are) that 4Mp is a little too soft for a 16x20 and who cares about the speed of 8fps when you are on a fine art shoot. Long gone are the days when you could use your Minolta SRT 101 for journalism, weddings, fine art and family snapshots.

Sid: Well, Nikon also has a 12 megapixel camera, the D2x.

http://www.shutterbug.net/show_reports/0105sb_35mmdigital/index1.html

But yes, the Nikon pro cameras primarily target news and sports photographers who need speed more than [b]ultra[/b] high resolution.

A lot of wedding photographers with Nikon systems use the D70, probably the best all-purpose model in the Nikon line. http://www.shutterbug.net/test_reports/1104sb_nikon/index.html

Cheers! Peter K. Burian, Contributor, Shutterbug magazine

It just seems that 4MP is a big light if you do some cropping. When you do an action shot, you might have a wide field of view to make sure you capture the fast moving action. Then, if you want to crop to the key part of the frame, you might be down to 3MP. I think it's a bit small, especially when Canon is doing 8MP at 8fps with the 1D2. 6MP would be more comfortable.

I think one has to look at the use of the picture. News papers and news magazines publish smaller pictures than we would hang on the wall, and newsprint isn't really capable of holding a lot of fine resolution anyway. The need for speed of capture and sending the pictures over the wire superceeds the need for resolution.

Why does it have to be one vs. the other? Canon seems to be able to integrate both (the 1Ds MKII), why can't/won't Nikon?