This week I've been getting to know Forefront Protection 2010 for Exchange Server and I thought this video on TechNet Edge was really helpful. Long, but helpful.
Alexander Nikolayev, program manager for FPE, walks us through how all of the anti-spam features work, including the new functionality with FPE over the previous version. After a couple minutes we dive right into the whiteboard walking through the mail flow anti-spam features with connection, protocol, and content filtering.
If you'd like, you can dive in to the FPE 2010 documentation on TechNet, which includes information on planning, architecture, deployment, and so on.