Yes, they usually offer it in the fall, but for 2011 it is from January through September. Whether or not it is a deal has been debated many times on these boards.
I wouldn't be surprised if you do see a big celebration towards the end of 2011 for the 40th Anniversary. I doubt it will be a free day or anything, but they will probably have special parades and parties. At least I hope they do something to acknowledge the 40th!