Sorry for bumping a somewhat old thread, but I never heard about this till now and got a little excited. I personally loved Sword Art Online and was a bit surprised to see this. However, I'm VERY disappointed in how NO ONE in this thread decided to use Google. It took me literally one minute to find the information regarding this. The developer is going to be Aeria Games, which did the Shin Megami Tensei game which I Personally loved. So that right away gives me quite high hopes for the game. However, their video comes off as more of a PSP title, instead of an actual free 2 play MMO.
Anyway, all the information is on the linked page, along with the "Trailer". Enjoy~
mmohuts(dot)com/news/aeria-games-leaks-news-of-sword-art-online-mmo