I got the following alert when I signed into my Gmail account after allowing Sina Weibo to access my address book:
Gmail Weibo accessed

Instead of using OAuth to access my Gmail address book, Weibo signed directly into my account. Needless to say, I immediately changed my Gmail password. With Weibo’s soon-to-be-released English version, I’d imagine this would scare a lot of people seeing a big red alert that someone from China accessed their Gmail account.