VMware just released vCenter server 2.5 u4 with the following improvements:
- Guest Operating System Customization Improvements – VirtualCenter now supports customization of Windows Server 2008 guest operating systems.
- Performance Overview Charts – VirtualCenter 2.5 Update 4 introduces the Performance Overview plug-in, which provides a single view of key performance metrics for CPU, memory, disk, and network without having to navigate through multiple charts. The aggregated charts show high-level summaries of resource distribution.
To install the Performance Overview plug-in, see Installing the Performance Overview Plug-In in VirtualCenter 2.5 Update4 (KB 1008296)
You can find the release notes here: http://www.vmware.com/support/vi3/doc/vi3_vc25u4_rel_notes.html