When I read the title of this thread as "Koda Kumi facing..." from the main page of the forum, I thought it was going to be a thread on her facing charges.
Anyway, I don't see what the big deal is. I don't really care if something is a rip-off or not. Besides, as Ryoko said, it's highly possible that two songs can end up sounding quite similar to each other. It has happened before, and it will always continue to happen.