Canon enforced their 
MAP (Minimum Advertised Price) policy on retailers. This prevents retailers from advertising at a lower price lower that the price Canon has set for the item. It seems 
Amazon, 
B&H Photo, 
Adorama have all "unofficially" dropped the price of the Canon EOS 5D Mark III body to $2,999. 
Amazon shows the price on their page. But for 
B&H Photo and 
Adorama, you have to add it to your cart to see the low price.