Now, about the tone - be a human first, programmer second. Even though it seems 10gen screwed up big time, everyone makes mistakes. You could inform them of what seems to be a major issue privately and politely, not ridicule them in public. I wouldn't want it done to me and I'm sure neither would you.
As said by Chazal (old timey Jewish scholars): "Proper behavior precedes the Torah ... and whoever humiliates another, it is as though he killed him"
EDIT: I'd just like to add that among the companies affected by this disclosure and which are now totally open to attack are Craiglist, Firebase, MTV, SourceForge, Codecademy and others. Here's the full list - http://www.mongodb.org/about/production-deployments/