The current 32-bit version of PM runs fine on 64-bit Windows, but modern processors are typically more efficient att running 64-bit code (usually around 10-15% faster is what I have heard, but this can differ a lot between different applications), so having a 64-bit version of PM would probably make PM even faster than it already is.
The disadvantage is ofcourse having to maintain two different versions of PM for Windows and I do not know how much work that would mean, but I am curious about if there are any plans for a 64-bit version?
An additional advantage would be the possibility to have a larger memory cache. In PM 4.5.1.1, the cache seems to be limited to 1024MB which is a reasonable limit for a 32-bit application, but with 64-bit it would be possible to use a lot more memory for caching if available.
// Johnny