Now days, I think that the majority of the PC gamers, with their ever more powerful hardware, have moved to 64bit operating systems to at least break the 4 GB RAM threshold. With the very near future of all PCs moving to 64-bit operating systems. With the extra resources and possibilities it has. Why would they not release a 64-bit exe for Skyrim. It being on the threshold itself. It would just add so much more possibility to the potential of the game and it's eventual mods. Anyway I am not an expert on 64-bit computing but I do know it is next months (stressing) future for computing. And we all know the potential it has. It is late for me. And I will be back later to edit this post if need be.
As of now Todd Howard has said there is not a 64-bit exe.