"Open Diary" as opposed to "Free Open Diary"
First, Open Diary isn't accepting any more free users. But now, Open Diary renamed its free service as "Free Open Diary," even though it's still not accepting any more free users. It seems that Open Diary is creating a new image for itself as a paid service.

There is a possibility that Open Diary may terminate its Free Open Diary and Teen Open Diary services soon. Right now, Open Diary is encouraging its free users to transfer their Free Open Diaries to the premium Open Diary service.

But why is the paid Open Diary service still limited to 10,000 users?