PerformancePoint Server SP2: Hyper-V is supported
IT Pro writer, Hal, wrote a great post about PerformancePoint Server (PPS) Service Pack 2 here.
I want to add that there is no better time than the present to communicate the potential cost savings that come from consolidating server hardware using Windows Server 2008 and Hyper-V. PPS Service Pack 2 now supports Hyper-V.
Consider the Sporton Lab case study where it reduces hardware requirements by a 1-7 ratio to reduce data center costs.
Consider the cost savings that Microsoft experienced (talked about here).
Hyper-V documentation
Plan for using PerformancePoint Server 2007 in a Hyper-V virtual environment