EOS 5D mkII, is 21MP overkill for most photogs?

It depends, I shoot mostly sports for web publishing and occasional newspaper, so a crop sensor xxD set to Medium jpg is fine. I'll still cut it down from 2-3 MB to 300-400KB so I don't choke the server during upload.
If I were shooting weddings, the 21MP would be more realistic.
Your milage may vary....

I guess Enrique you don't frequent forums much. Most people buy these types of cameras to pixel peep and argue around noise artifacts on forms. The 21MP of the 5DII keep these photogeeks outta trouble for weeks at a time...

Overkill? Apparently not. And if you consider digital backs, some of which are up to approx. 60MP, 21MP is child's play!

I do appreciate that 21MP allows me the latitude to potentially crop more aggressively than I could with my 30D. I have not noticed a significantly slower transfer/processing time. More disk space used, absolutely! That's why I frequently cull the obvious duds.

Demands vary, and I'd always rather have too much than too little if IQ is a primary consideration.

I'd always rather have too much than too little if IQ is a primary consideration.

Do the number of mega pixels actually determine primary image quality in a printed photograph? I think not. But this could be an interesting debate.

When I started taking photographs in the DSLR format, I began by purchasing my first canon 30D. Since before I actually moved on to FF I was of the believe that a "better camera" could improve my image quality, but to my dissapointment (when purchased 5d and 5DmkII now) it did not and I went to actually improve my pictures and image quality by taking creative ligting lessons with flash and the art of composition in my local community college. I have seen many great photographs shot with a digital rebel all the way up to those expensive digital MF. But I have also seen many, many crappy shots taken with an eos 1d's mkIII and eos 5d mkII.

My thought and why I stick with the 5d 12m was, how many pixels it takes to print a standard wedding shot at 5x7. all those pix get shredded ? the option is there for smaller Raws to try. pixel peepin might omly tell the diff, doubt if std size prints will ;0)

I for one would prefer lower resolution with larger photosites, even better low-light performance and less artifacts in video. But we have to take what Canon offers, so there's little point in waging lengthy discussions about what the Mark II should have been.

"even better low-light performance "

Not necessarily. The amount of light collected per unit area of sensor will be the same, so it's not clear that you actually lose anything by collecting that light in 4 or 8 pixels. If you shoot at, say, ISO 12,800 (according to an external meter, using the optimal in-camera ISO setting) and downsample both a 5D and a 5D2 image to 6MP, you'd see a lot less difference than if you compare the individual pixel performance. Similarly, you might like a noisier per-pixel 21MP image printed at 300 ppi (12 x 18) better than a less noisy per-pixel 12MP image printed at 240 ppi (12 x 18). That is, in making an actual print, there are pluses as well as minuses.

But the 12MP 5D made a very nice 12x18 print, and it's not clear that there's any need for 21MP at 12x18.