Yes! WIA-Loader works on 64bit systems, there are a few things to know although.

The Canon RAW SDK can not be used with WIA-Loader on 64bit Systems. This means, for canon raw files (.crw, .cr2) some meta data (like EXIF) is not available during import. Also, in some cases, WIA-Loader is not able to display a thumbnail for these images.

On demand i could provide a special version of WIA-Loader that runs in 32bit mode on 64bit systems. The canon RAW SDK is available then, but as a drawback, WIA-Loader will be a little slower then. I'll publish these version in the forum when requested.

Another problem on Windows 7 64bit is the nikon nef codec. The original nikon codecs doesn't work there, so you have to rely on third party codecs.