Update: this rumor got busted! The source admitted that it was a hoax (he got banned from this blog already). There was not much I could do - this is a rumor site after all and if you read the comments to this post, you will find out that this was not such a crazy idea.
The rumor of the year:
"Nikon will have a new Firmware ready that will upgrade all existing D3's to 24.4 megapixels. The 24.4 megapixels Sensor sits in the D3 since day one. Nikon worked hard on the software to get identical files (quality wise) out of the 24.4 MP like the existing D3 files. The other reason for the release of the D3 with 12.1 MP was a contract with the sensor manufacturer (Sony).
There will be a Desk at Nikon's Photokina Booth where visitors who bring along the D3 can get the update immediately! The Firmware will be available AT NO COST after Photokina @ Nikon Homepage."