This is a great set of resources from Jeff Carr that expands upon the information I posted earlier on the PerformancePoint Planning and Architecture Guides.
Jeff's taken this one step LEAP further - This is your PerformancePoint Bible:
Help, How To, Guides, Manuals, & Forums
Planning Help: How do I ...
Monitoring Help: How do I ...
Guides and Manuals
User Forums on TechNet
This is a GREAT resource for both customers and partners.