It's all related to computer upgrades for Aulani I think. As Disney4Shaw posted, there's been a notice on the DVC site:
"
The opening of Aulani, Disney Vacation Club Villas, Ko Olina, Hawai`i is on the horizon! In preparation for opening on August 29th, Member Services will have limited system capabilities from 9 AM - 1 PM EDT on June 7th. Self-service functionality on DVCMember.com will also be unavailable during this time frame. Please watch DVCMember.com or call Member Services for exact hours and updates about the integration as new information becomes available."
I'm just assuming the dining system is being upgraded along with the DVC system. Sucks, tho. I REALLY don't want to make ADR's over the phone, and it sounds like making over the phone isn't going to be qa peice of cake, either.