I wrote about this before – so no point in rehashing. Real ID is being implemented exactly as it was proposed months ago, with the same security concerns.
Read what this feature does. If you are feeling a bit queasy about having your real name “out there,” then don’t use it.
Those of you who want to use this feature, don’t be offended if someone chooses not to friend you. It does not mean the person does not like you. There are some serious security concerns that would cause many people to err on the side of caution.
I will not be using this feature at all. If I want to cross-server chat, I can do so via gmail or any other IM program: without divulging my real name to anyone, especially not friends of friends, and without the security concern of giving out my battle.net e-mail.