http://www.groovypost.com/wp-content/uploads/2013/12/Hangout...
http://www.groovypost.com/wp-content/uploads/2013/12/Hangout...
The second link is just a screenshot and I see nothing concerning 'identities' there. It wants to replace SMS and you can accept or deny? Granted, one should click on that learn more button before accepting that - I don't know what hides behind that link.
Maybe it is the first link you posted? That .. doesn't seem to say a thing about identities either, unless you mean the single paragraph about being able to select among multiple accounts, should you be signed in to more than one?
I didn't watch the video, maybe that one offers more, but so far I don't think FUD is the right term here..
The fact is that Google have made keeping personal data and private activities among various Google services all but impossible. I had my unrelated G+ and YouTube accounts outed and linked despite repeatedly rejecting the joining of them, in November 2013 (resulting in 3 simultaneous top-o-the-page HN stories at the time).
I'm calling shill or FUD here.
I think if there's anything I'm not buying into, it's a new account which seems to only exist to promote Hangouts / google+.