As a team member, she oughta reign this in a bit. As a company founder, saying what you think can sometimes hurt your company. I think you have a duty to put a buffer between your brain and your mouth, especially around touchy subjects. If you always say what you think around investors and customers, you'll probably have fewer of both. :-)
I think a lot of people (PG included) have remarked that founders are ALWAYS selling (to customers, investors, new hires, reporters, etc). Part of selling is the ability to anticipate a reaction before you say something and to say the things that will elicit the reaction that you want. Or, at very least, speak the truth in such a way that it maximizes the effect that you want and minimizes the damage that it might cause. Example: last night I ate a juicy organic steak vs. last night I ate a muscle tissue sample of a castrated bull (hat tip to Robert Heinlein).
We all make mistakes-- I HOPE she realizes that there's a reasonable chance that she (and her company) might have been better off if she hadn't said what she did or said it in a different way.