Yep insanolord is correct, this just means that if you have stars in your account balance that are more than 2 years old, redeem them now or you won't be able to soon. Otherwise the stars system cotinues as normal. They can be used to purchase bits of Nintendo merchandise from the Club Nintendo store, like caps and tees, remote control Mario Karts, stuff like that, as well as Wii Points at a 4:1 (Stars:Points) exchange rate.