I will be a great feature in RadDatePicker to choose formatting of date for example only by year or month and so on... - like in DatePicker for Windows 8 Xaml version.
When I have in the RadDatePicker some date value (ex. 1.1.2013) and I try to change only year so, that I use dropdown window. When I select Year (ex. 2012), it goes OK. But when I change same month as current selected date, it open date calendar on January 2013. If I make same, but change different month (ex. Feb) it open date calendar OK.