I appreciate the thoughtful way you've gone about this, Rodrigo, and that you have listened to people's concerns and are tentatively committed to trying to work out a feasible way to support private game functionality, even though a lot of people are in favor of ditching it or don't care. Sometimes majority rule means tyranny of the majority, and I really appreciate that you've taken into consideration the valid concerns of the minority, even at considerable cost to your team in terms of time and headaches.
In response to drkrough, a lot of us are in a position in life where we have to worry about potential employers googling to check out our online activity, and whether or not we are ashamed about our gaming habit, employers might look at average posts per day and decide we're liable to waste company time, or just throw our application out of the pile because we're into a hobby that marks us as . . . whatever their stereotypical perceptions of gamers is.
Of course for those in that situation, you should always use an alias on sites like this that won't instantly connect your real identity to the site. I am also careful not to use my fellow gamers' real names when chatting with them OOC, for similar reasons. A dedicated investigator could probably figure out a lot, but it keeps someone from casually typing our real names in and finding out that we are gamers and post an average of X times per day on this site. I suspect, though, that our high school, college-age, and twenty-something members don't always think of these issues when they create an account here. The same may go for people who come to this site to participate in a private game with RL friends using a real name as username (or merely casually calling each other by real name in the game's OOC thread) and suddenly discover (if private game feature were to go away, which Rodrigo has just said he doesn't think will happen) that a google search for "John Doe" reveals their marital/family status, city of residence, favorite hobby, and the fact that in his gaming group's d20 modern game John is playing a seductive blond actress who is dating Steve's studly private investigator, not to mention that John posts to MW an average of 4.5 times per day and was last on the site at 10:30 AM. That might well be enough to get John's application for a new job tossed into the "eliminated from consideration" pile, even though none of it has any legitimate bearing on his job qualifications. Much of this info has only been voluntarily posted by John on this site, but if you're using the private game as a substitute for RL tabletop meetings for your group, you're likely to carry on as you did IRL, and if you can't do that, it takes some of the magic out of the site.
This is only tangentially related to the private games feature, but I think "web profile maintenance" is as valid a concern as "privacy," and "web profile maintenance" is not about whether you'd be publicly ashamed of what you posted here, but about how your personal brand fares in the job market. Obviously, folks should consider using aliases when they set up their accounts unless they've already retired, gotten tenure at a university, or become a senior partner in their law firm, but even with aliases, I think it is entirely reasonable that many players might want to have their friendly chatter with their friends not be exposed to the public gaze, for all kinds of reasons that have nothing to do with keeping site content appropriate for all viewers.