From Wizards’ recent Premier Play announcement:
“Expanding the schedule has brought unprecedented access to the Grand Prix experience, and players are making the most of it by turning out in record numbers. To adjust for this growth, starting with Grand Prix Indianapolis in December 2012, we will be extending Pro Tour invitations (and airfare) to the Top 8 players if a Grand Prix has 1,200 or more participants.”
In related news, winning a PTQ will now provide a 1,000 point bonus to that player’s seasonal Planeswalker Point total. This is intended to address the limitations placed on a PTQ winner’s potential to accrue Grand Prix byes, given they can no longer participate in PTQs to earn points.

