I believe that because of security reasons, unplugging the ready boost flash
drive in standby mode will cause the cache to need to be rebuilt. When
hibernating, after coming out of hibernation the cache is rebuilt just in
case the cache has been compromised. Maybe version 2.0 would allow a user to
configure whether to rebuild the cache after coming out of hibernation.
Only ReadyBoost memory that is built into the motherboard does not present a
security problem (to a degree) and does not have to be rebuilt each time
after coming out of hibernation.
Service Pack 1 (available this month) might help with the problem that you