This actually has been available for a couple months...great OS if you have the PC to support it. There are a few words of warning before you convert tho...most importantly make sure you can get drivers for all your devices. My machine had no issues, other than no drivers for Logitech cams yet, but no biggie there.
If youre interested I suggest reading www.planetamd64.com forum before making the plunge. I also suggest dual booting for awhile to make sure everything works