I was thinking the sticky point with compatibility might be the older drivers for the peripherals, such as the Fujitsu Snap Scan driver, the Brother MFC driver, or other items. So all of you running 64 bit are not running into these problems? Any issue predicted with running a 64 bit 'server' copy of Windows 7 Pro with other machines all using 32 bit? Or will I need to upgrade them all to 64?
No your workstations do not need to be 64 bit. Most companies have made 64 bit drivers for their products anyways. Just be sure to check your hardware prior to purchasing. If there are no drivers for it, simply move the device to a work station, problem solved. You can always check the manufacturer's website prior to upgrading. For example, Fujitsu has a list of models for which there are drivers for Win 7 (32/64):
http://www.fujitsu.com/global/support/computing/peripheral/scanners/ssfaq/win7.htmlI've had no problems running SBS 2011 64 bit with our 10 XP Pro 32 Bit work stations. Even at home I have 2 Win 7 computers and 3 XP computers and they all share files and printers.