G+ unfortunately lists the formal description of a "common name" as being "what your...friends...call you" which is not what Google's hounds are using for people involved in the SCA or in Second Life or for folks who have been using handles for their technical professional work (like skud) for (in some cases) decades.
Look, most of you think I don't have much skin in this game -- I have thirty years of skin in this game. Maybe a little more foresight and effort...:)
Just to give you folks an example, most of you probably don't know that my passport and birth certificate list me as Elaine Marie Nerad. On the last page of my passport, it lists, much to my umbrage "aka Shava Nerad." They told me, "Hey, don't sweat it, Madonna's has an AKA too." Most of you have only ever known me as Shava, and for most of the people reading this, I've been Shava your entire lives.
I changed my name to my use name, my "handle," the diminuitive of my Hebrew name (Elisheva) in 1981, legally in the commonwealth of Massachusetts. My first technical paper was published under the name Shava Nerad when I was twenty-two, that year. There were Chavas and Sharas and Shiras and even a Skia in my circles but I was the only Shava I knew, and I rather liked being (for some long time) a unique identifier. I suppose these days, they'd call it a personal brand.
Much later, as more Shavas came onto the net, I became shava23 most places. This is the way the web works. This is the way we find one another. This is the way naming works for those of us who are digital natives -- and I'm an elder among digital natives.
If I hadn't done that, and I were skud's age, I could be in skud's position today.
I consider my name, after thirty years, to be my real name, and so would just about anyone else. I pay my taxes under it. My social security card reflects it. My credit rating is under it. Only my birth certificate and my passport remember my birth name. It is more real than a couple of married names that have come and gone in thirty years.
Now, if Google wants to create a social network for non-natives, maybe that's a bigger market share. But telling digital natives that we are the people who walk into restaurants with our shirts off? Why thank you, -- I just got the warmest fuzziest feeling about your sympathetic view of an entire cohort of people under 35 or so years of age. And including myself at fifty-two.
May I suggest that it may be an easier job to educate the boomers to understand their kids' culture than to build a social network for boomers? Even in Snow Crash, which was written on a typewriter in 1984, the understanding of how naming conventions would evolve in a digital world was more evolved than this.
It will be easier to make older and less bi-coastal people comfortable with nicknames and foreign naming practices, I think, than to stuff the entire world's naming practices into this tiny narrow draconian rule set, and have to enforce it.
You can certainly look at the naming policy of, say, online communities like Turbine's Lord of the Rings Online (lotro.com) to avoid the mess of, say myspace.com. You can create filters that prevent "bad words" and certain forms of punctuation. You can create reporting mechanisms. There are many many options.
You can even tell the people who believe that "real names" are the only authentic people, and all the other self-named people are dangerous and liars, and make it so they only see the "real" people. That's a bit in their preferences. These days, that makes them shut into their own ghetto, because you know what? Online, they are the minority. If it makes them more comfortable, help them throw up walls around their own protective ghetto.
If there is anything that this world of globalization and games and cultural diversity has done, it has shown more and more people every second that "real" is just bigger and broader and stretchier than what they thought it was yesterday. And of all the multi-national companies in the world, Google would be the one who I'd expect to embrace that.