Just a quick note for those thinking about installing the 64 bit. I just installed it, an the installer looked at everything I had already set up. I did not have to use any wizard to point to my existing library or re-load my plug-ins. Kovid designed it so that if you had a preexisting installation, all the libraries and plug-ins from your 32 bit would be immediately available in the 64 bit. Since Kovid originally said that the two versions could be run and installed at the same time, I had made the assumption that the 64 bit would require configuration upon installation even if you had the 32 bit version installed. It didn't require any special configuration and it's working great on my system so far.
I must say a huge thank you for making the installation seamless and stress free.