To the tune of 167 Million accounts. This per the warning I just got from my internet security software:

At the very least be wary of new spam and scam emails coming from people claiming to be with Gravitar, or anyone else. Fake blackmail schemes claiming to have more data on you than what was breached, or to have put malware on your PC are also common scams.
Spread the word.
CHANGE YOUR PASSWORDS, HERE AND AT GRAVITAR!