SiliconVoid said:
I don't mean to be the proverbial rain on the parade... but the best answer to your inquiry IS what someone wants to pay for it.
Not quite. The market clearing price is the price for which the number of willing sellers is equal to the number of willing buyers (where supply and demand curves cross).
The fact that some might not be willing to cough up $1800 (or $180 for that matter) for that body does not mean that he has to sell it at that price.
Any pricing you have seen in the past for the 5DmkII, or see now, has no significance - they are for a used 'current model'. After the new model is announced the resale value will decline noticeably on used, and will likely steadily decline on the remaining new inventory until they are gone.
The announcement could affect supply demand, we can speculate on how this will play out. It will depend to a large extent on pricing of the new version.
I don't think 1500-1600 sounds right -- not consistent with completed transactions I see in the used market right now.