Finally an official announcement from Production IG!
There will indeed be a second season of Ghost in the Shell Stand Alone Complex (Currently named "2nd GIG" in the traditional Engrish way)
http://www.production-ig.co.jp/anime/gits4/
From what I can translate it will be a further 26 episodes (as previously speculated) airing on the Skyperfec channel in Japan from January.
If anyone can further translate this page it would be appreciated.