Are you planning to purchase hardware for implementation of the Hosted Messaging and Collaboration solution?

Microsoft strongly recommends that you select servers with 64-bit processors for the hosting services platform servers.
The large memory access and processor speed improvements provided by 64-bit servers provide the most cost-effective approach to data center requirements.

Most importantly, 64-bit servers enable performance improvements today for 32-it applications while also ensuring future compatibility and a longer lifespan as more and more data center applications become optimized for 64-bit architectures.