Well, that seems to be a bit strange. Here's the link to the Qantas site regarding to status benefits:
http://www.qantas.com.au/fflyer/dyn/...atusPrivileges. It does say here that Priority check-in (regardless of the class you're flying) for Silver can be done at Qantas Club/Business Class counters. This is a good summary of all the benefits...perhaps we should all carry a copy when travelling to ensure we get the treatment we deserve!