We were just there in September and Starlit Hui was on Monday and Thursday nights only. During the current expansion/construction project, it may be temporarily suspended because they are using that area to build something else. Because of the popularity of Starlit Hui, it is being moved to a different grassy area that is larger. According to the Disney Aulani website - ...To accommodate more Guests, there will be a new, larger lawn location for...the nighttime Starlit Hui hula showa popular Guest experience. The new lawnHālāwai Lawnopens October 8, 2012.
They have not announced yet if it will continue with no changes or if they are going to alter the program. This phase of the expansion/construction is scheduled to take a break sometime around Christmas but will not be complete until mid-2013. You can call Mbr Svcs or Aulani directly in January to see if they have changed the nights for Starlit Hui.