I would encourage the readers of this blog not to give up on Scalable Networking Pack because of these issues that have primarily to do with a single driver from a single vendor. The fact that SP2 was released with SNP features enabled by default was accidental (just ask Microsoft, and witness that they are disabled by default in Server 2008). TCP Chimney and RSS both potentially offer performance advantages in an Exchange environment if they are implemented correctly (though non-page pool memory usage may continue to be an issue).
Disclaimer: As an employee of a TOE vendor that is not Broadcom, I am certain to be biased.
Microsoft
