Sorry to have bothered you, found it. On the AuditReader, there is a method named getCurrentRevision(). I had seen this method, but what threw me off is the fact that you need to specify the class you use for your revision info.
The following will get you the current revision to which any entries in the audit tables will be bound:
RevisionEntry revision = AuditReaderFactory.get( entityManager ) .getCurrentRevision( RevisionEntry.class, true );