It is worth noting that the dates have been shortened (compared to previous years) to end on Oct 28, 2011. Was hoping it would go through until the first week of November.
Virgin America Day - Saturday, August 6
All fans receive 2 for 1 flight voucher
Valid for travel Main Cabin between 8/16/11-10/27/11.
Blackout dates are 9/2/11 and 9/5/11.
Must book by 8/31/11, with two passengers travelling on one itinerary.
http://mlb.mlb.com/sf/ticketing/virgin_america_day.jsp