I believe this should be achieved through use of emulators so we can simulate every aspect without actually involving other people and/or hiding personal details such as real names, phone numbers, etc.
With a test instance we can just make them all up 
I’ve deployed a test instance a few weeks ago when I said that any account you should need, we can provide a personal key for it.
So I’d say, whoever will take charge of this, I’ll provide him/her some accounts to do tests with some emulators.
That being said, if someone wants to do this with real people and real conversations, he/she is welcome to do so, as long as he understands that it could be viewed by thousands of people 
One more thing: screenshots will be actually uploaded only when 4.0 stable will be released (Google Play doesn’t allow screenshots for beta releases).