I think GM shot themselves in the foot regarding selling price ever since they offered the XLR at the "You pay what we pay" sales promo. I would think you could and should find a dealer that will discount. Good Luck..
I would agree, a friend of mine who spends quite a bit of time at the auto auctions tells me the 2004's are coming through anywhere between $47,000 and $51,000, sometimes more depending on condition. Cadillac dealers who take them in tend to hang on to them, but most of the others run them through the auctions.