I just started playing with the RCs - I noticed it says unloading geometry during the lightcache. Is this a new feature to save memory?
It is not a new feature, V-Ray has been doing that before as well, when the amount of dynamic geometry overflows the limit specified in the System rollout. There is just a message for that now. If you see this message too often, it may make sense to increase the dynamic memory limit.
Best regards,
Vlado