We've got the following on our servers:
"ERROR_SHARING_VIOLATION" error message in Windows XP or in Windows Server 2003 when you try to open a file on an SMB share on a server that is running Windows 7 or Windows Server 2008 R2
A robocopy command updates DACLs incorrectly in Windows 7 or in Windows Server 2008 R2
Slow performance when you enable IPsec encryption on a specific TCP port number in Windows 7 or in Windows Server 2008 R2
A hotfix that lets you diagnose mini-filter-based performance issues in Windows Server 2008 R2 is available
SQL Server data corruption when a memory range is accessed by the SetFileIoOverlappedRange function and an I/O operation in Windows Vista, in Windows Server 2008, in Windows 7, or in Windows Server 2008 R2
SMB commands run serially when the SMB packet-signing feature is enabled in Windows 7 SP1 or in Windows Server 2008 R2 SP1
"The file or folder does not exist" when renaming or saving to DFS share from a Windows 7 computer
Home folder is not mapped to a client computer when multiple users are logged on to a computer that is running Windows 7 or Windows Server 2008 R2
"0x00000050" Stop error in Windows 7 or in Windows Server 2008 R2
Computer stops responding after you connect to an SMB 1 server in Windows 7 or in Windows Server 2008 R2
High CPU usage on a file server that is running Windows 7 or Windows Server 2008 R2 with ABE enabled
Several of these are client side fixes, but since Windows Server access another file server is a client, I figured they out to be at the same patch level as the rest of the clients.
I have not had *ANY* complaints about network performance since we deployed these updates to the servers and client.