Giving this thread a much needed update.
SDN gave a performance for the stage revival (which for those who missed it is a one time performance of the old stages) and it has been announced that Tojima Hana and Komatani Hitomi will join SDN48.
For those who don't know who they are Tojima Hana and Komatani Hitomi were 1st Gen Team A members in AKB48.
Here are blog updates with information on the songs performed and pictures.
http://ameblo.jp/akihabara48/entry-10905164849.html
http://ameblo.jp/akihabara48/entry-10905203979.html
http://akb48.blog48.fc2.com/blog-entry-4813.html
Let's hope this and the other stages get released on DVD.