Basic identifiers to my knowledge
I'm getting a lot of messages regarding what I know of Real IDs. I can elaborate on what was considered months ago as that's the last time I got any information (aside from public) of what it could be. There are things that could be different but I figured this would be a way to help alleviate some time spending. I understood 2 different potential formats:
Format: Character.Account -or- Displayname.Account
Now, moving on with some public knowledge we later found out, it sounds like there is going to be a limited number of "Characters" per "StarCraft II Account". For this reason it leads me to speculate that the first one is most likely.
In that case, for your account you'll have 3 or so "Characters" you can create for StarCraft II. Let's say for me, I use an account name of "UBERSCLGUY". This would be a unique identifier. If I find out that someone else, like LordofAscension, took that identifier I would have to pick another one. This is not unlike signing up for an IM account, as you can't pick an account name that's already in use. For that reason, I'm going to proceed in this example as "UBERSCLGUY1234" to help elaborate that point.
Now, I have the ability to make 3 characters in my account. (from information that may be out of date) One of my characters will be "Gifted". This is not my identifier, so it can be one that others see as well. At this point, if I were to log into that character, it would be "Gifted.UBERSCLGUY1234". If we return to the mentality of IMs... While I have an MSN account with a unique email address, my display name is not that but rather "Kevin" or a variation thereof I can change if I want. For this reason, when I talk to my mother, I don't see "Grandma@emailaddress.com says:" but rather I see "Mom says".
This previous point goes MUCH FURTHER when you take the perspective out of StarCraft II. If you look at cross communication regarding SC2 and WoW, it makes a lot of sense. Let's pretend that LoA plays Diablo 3 in the future. When I'm trying to contact him, and he's playing a Barbarian named Conan... He will be essentially playing "Conan.UBERSCLGUY". If I were playing WoW while he was playing Diablo 3, he would see something like "BobtheGnome.UBERSCLGUY1234".
Display/Privacy settings to my knowledge.
Now, when you move forward knowing what you know... there are three levels of privacy that I am aware about. Much of this has been recently brought to light in blue posts. But it would be nice to elaborate on these.
The first level of privacy is the "Character" level for lack of a better description. This is what happens when anyone tries to friend you that you barely know. This means they know you on the CHARACTER level and only know your CHARACTER. In World of Warcraft, it would mean that a person I would randomly group with who likes me would know me as "BobtheGnome". If I were to log into another character, they would have no clue. This is how WoW currently operates.
Second level is a "Player level" where they get to know your "account". This allows them to see your account name.. and further, whatever character you're on. In World of Warcraft, this is essentially letting people know all of your alts. In the more global scale, it also means that people can get ahold of you no matter if you're in another faction, server or game.
The Third level is a "Real Life" level. This means that people can see your personal data, such as real life name. This would mean you could see me as "Kevin ************" on your list and know whatever game I play.
There are other levels and customizability in each. For example, this doesn't include the "ignore" level.
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I hope this alleviates some concerns and questions, and please understand this is a combination of public understanding and a conversation I had with JD literally months ago. I know that "clan tags" will be separate in some form and can't even speculate on it other than that fact.
Please feel free to ask questions, but I don't know if I can answer any information further as I think I've explained well what I know, but if further elaboration is required, feel free.