I've talked to our Apple Rep about this; in FCP HD you have the niffty refresh A/V devices but nothing in Motion. He indicated that this feature will be added in a future release of the software, ie 1.5 or 2.0 depending on how they go with Motion.
Damon Casantini
Advanced Systems Integration
Applied Video Technology
http://www.appliedvideo.com
Apple Pro Video Technican
Avid ACSR: Windows