On December 7th, Sega announced via their official blog that owners of Sonic Generations digitially via Steam can enjoy the Casino Night DLC beginning the day after Christmas, at a reasonable price.
"This gives players a pinball mini game, set in the Casino Night stage, to enjoy alongside the main game. It would certainly make a perfect little stocking filler for Christmas!"
The DLC will go live everywhere the same day. It will cost $1.99 in the United States, £0.99 in the UK, €1.59 in the rest of the Euro zone, and $2.99 in Australia. No guidance was given as to when the DLC may drop for home console orders who didn't pre-order the game.