CS4 Learning Centers at Layers & Photoshop User

Layers Magazine has a CS4 Learning Center with video reviews and tips for most of the CS4 applications, including After Effects.

Also, Photoshop User has more specific video at its Photoshop CS4 Learning Center. In particular, check out the less flashy new features like the Adjustment Panel, Dodge & Burn, On-Image Controls (also works in Hue/Sat and Curves), Live Brush Previews, and the Mask Panel (with dynamic edges).

Update: Richard Harrington is posting a growing library of video on Photoshop CS4 in different places, like his CSFour.com.