That Maria one isn't for 2012. It was specifically designed for her 2011 YEC and as usual all her dresses have the 2 pieces version for her minions to wear and also for her to wear the next few non-grand slam tournaments. Hence I believe Maria will wear 2 pieces version of her 2011 YEC outfit in 2012 Brisbane. But it's still part of her 2011 collection, not 2012.
Her collection for a particular year always starts with her Australian Open dress.