I just did an unscientific check at Jpop Central (since a lot of the former JPM diva-crazy fans seem to have settled in there). The two most recently active threads are for Hikki and Namie.
And in general, the focus is on similar oldies. But Nishino Kana and Wakeshima Kanon also show up in the first 10 threads -- they are, if not recent, at least less unrecent, I guess.
All in all, though, it does like the Jpop diva world has fallen on somewhat hard times.
If madness made us strong, we would all be invincible.