So, if they are giving it away, how will they make money? I understand how Google make money, and I have an uneasy truce with them, that I'll surrender some privacy and they can give me a free phone OS, and other "free" stuff like search and maps.
Bur Microsoft, make money from "free"? How? They bought aQuantive for billions, and shrivelled it to nothing in a matter of months. Bing? Yeah, make me laugh. Even to get their hands on a mapping system they had to spend billions buying a phone hardware maker. And their track record of giving things away has been pretty bad - they gave away IE for "free" to destroy Netscape and others, and look what that got us - the worst, least secure, least standard compliant browser for the subsequent decade, and resulting in the baked-in IE6+XP mess that left dopey corporates unable to migrate to proper browsers or upgrade their operating systems.
So we either have MS making a success, crushing Google, and then leaving WP to fester and decline for the next ten years because there's no money coming in. Or we have MS continuing to limp along, selling modest but loss making numbers of phones to those who don't really care about their phone OS, whilst the masses remain familiar with and preferring IOS and Android.
Quite frankly you could plate WP 8.1 with solid gold and supply it in a pouch made of unicorn skin, and I wouldn't touch it. But I'm sure the kidz will be happy if it's cheap.