I don't trust anyone except may be a RIM official for this type of news. Even the first rumor about RIM developing a native DM, I don't trust. I sure there is one internally but people who receive calls or emails from us are not the one who has sufficient amount of responsability to have a general vision of RIM's activities, especially development part.
Someone at MacRumors posted back in early June that he knew a beta tester; if true that means we are nearing 2 months of testing (at least). I'm still predicting October, but I am going to email [email protected] every day in hopes that I will catch someone who will slip up and give me some info.