I purchased VSTO 2005 shortly after it came out. It cost about $700. I think it was one of the choices for purchasing Visual Studio. As I recall, the comparison chart had Visual Studio Professional for $700 as compared with Visual Studio with VSTO also for $700. One of the key differences seemed to be that I couldn't use the VSTO product to develop for 64 bits.

Assuming that I understand that part correctly, does this mean that I can't upgrade my OS to Vista 64 and continue to run VSTO on it That is, is there some sort of 32 bit mode that will let me develop on Vista 64

I'd really appreciate any help in clearing up my confusion here.