we recently had a client have us do research on why it did not appear all updates for a few of their projects were being published via the AutoPublish functionality provided as of SP1 for Project Server 2010.  Prior to researching any issue I am always sure to replicate it first.  Well I certainly was able to replicate this issue provisioning an instance of Project Server 2010 with their databases in MPN’s datacenter.  After some additional research, I noticed this behavior was also happening in our base Project Server 2010 environment.  Thus far I have not been able to determine a consistency or resolution.  If anyone has any insight on this we’d love to hear from you!