Jim Wightman's blog posting on SCCM not natively being a 64-bit app has been on my mind for a while now. I'd like to wave a wand and magic up a 64-bit version of the production today, so that we can leverage even more performance out of the OS and Hardware. But realistically, it won't arrive until the next major product release as it cannot be fitted in to an R2 or service pack release.
Good points though Jim, this stuff should get back to Microsoft
Read the complete post at http://wmug.co.uk/blogs/r0b/archive/2009/01/05/sccm-64-bit-wowness.aspx