Just to clarify Sean's response for those that don't know....all actors are placed, automatically into a category based on billing. (Above or below the title)
If the producers want the actual size/impact of the role to be considered for placement instead, they petition the officials. 3 (or is it 4?) times a year, the committee sits down to discuss and make a determination. You will notice the announcements from those meetings will mention any changes, and then blanket the rest with a comment like: all others will be considered in accordance to the rules.
If we're not having fun, then why are we doing it?
These are DISCUSSION boards, not mutual admiration boards. Discussion only occurs when we are willing to hear what others are thinking, regardless of whether it is alignment to our own thoughts.