William,
a friend of mine just got the LS 460 with navigation...he went all over town and heard the same thing you were talking about. Nobody wanted to move from MSRP including JM on the 08. Then he went to pembroke pines way out west and his salesman alex was able to give him 4k off the sticker...so i would have to recommend him if you are in the ft. lauderdale area.
Actually, I just got thru negotiating with JM in Margate and was offered the '08 LS 460 for 7% off MSRP... just about the same deal your friend got. The salesman also said he could deal much better on an '07 as they had a lot of them to move. Problem now is that I am stuck with my '01 Ultra and they want to rip me off on it, so I'm trying to sell it privately. -W