Re: Just Saying...
"I accept that I only have MS's word for it"
That's not worth a lot, it it? As in Zero, Zilch, Nill, Noll, Nada, Nought, Null, 0.
If all things that are potentially monitored are sent to the mothership, but only stuff that you asked them to track actually is shown to you, where do you think the supposedly non-retained data ends up? We know data must be retained, by law, in various places, and we know companies, such as MS, are required by law to lie to their customers about any security related issues.
Even if not all is retained today, it's a certainty that it is being mined for "terrorist" related information. Of course, having the snooping agent in the actual OS itself is much better than trying to look at encrypted data just passing by. The OS is then both a snooper, and a controllable component that can be remotely reconfigured on demand for further investigation. NSA must be having their wettest dream yet.
No, I'm not a terrorist. Honest. But control-freak states seem to have a tendency of getting out of hand. "1984".
And the above was only about the state-sponsored potential snooping. Then we have all the annoying ad related selling out of your information crap, with related potential security issues. Not to mention sucking your battery dry with unwanted CPU activity, both from spying and from then delivering the animated sh*t to your screen.
Brave new world!