Price guestimates for the 200-400 will be closer to the $12K mark I think. I can't see Canon bringing out a competitor for their 500/600 f4 at much less than that.

I think you may have to rely on Sigma to come up with something more affordable in the 500mm range. There will be a lot more people willing to part with 2-$4K for a wildlife lens than the $10k minimum buy in option from Canon.

I have nearly purchased the 50-500mm so many times now.....