As Nikon prepares to reveal the Nikon D6 flagship DSLR in earnest, the Nikon D5’s price has dropped to an all-time low. Whether you want the XQD or CF memory card version, you can now pick it up for “just” $5,497, or a full $1,000 off the suggested retail price. By all accounts, the Nikon D6 will be a major upgrade over the current D5: with rumors swirling of in-body image stabilization, better video capabilities, and other features that will…