Just got back from the shop. Can't say thanks enough to Nate for getting this thread back on topic.
It seems as though the HD800 may really have a lot to offer. I'm dying to hear them, but I can't see myself jumping the gun until I've had some time with them.
I have no doubt that Tyll's review is spot on. He's about the most trustworthy headphone salesman one could ever hope for, but I'm not sure what the rush is all about. However that tends to be the way with all new phones of interest.