The 5d will be the main camera for myself, i want a full frame for the most use, and the camera i have now will become the backup, the main reason im looking for a second body at the moment is im going to the MotoGP in October at Phillip Island and dont want to be changing lenses while im wandering around. I did this at the Clipsal 500 this year, and hated it, i want one body to have my zoom on it for on track shots, and the other to have a small lens on it to take off track shots (cars in pits etc).
I will search the 40d problems, and go from there, i have been offered the use of another 400d for the weekend, but would still like a second body, and originally wanted the 40d, but couldnt afford it in time for the Clipsal weekend, so the 400d was settled on, if i decide to wait for the 5d and not buy a second body, ill just spend more money on other parts of my kit in the meantime!
Cheers
Chris