- Microsoft owns Pando Networks, famous for the malware/botnet Pando Media Booster.
Windows Update in Windows 10 utilizes P2P by default, most likely the same P2P technology used by Pando Media Booster.
Essentially it turns your PC into a zombie host server, wasting your bandwidth serving updates to other computers.
This also means Windows Update might be utilized later to spread malware through the P2P system via 0days.
- You cannot turn off "Telemetry" unless you own Windows 10 Enterprise Edition.
This means your computer will continuously leak unspecified information to Microsoft and there's no way of turning this off.
- You cannot turn off "Real-time Protection", aka Windows Defender. Even if you do it will turn itself on again after a while.
This means you cannot prevent your PC from sending random files and information to Microsoft for "analysis".
- Cortana has zero local storage functionality and does not function unless you have a Microsoft Account connected.
It will even inform you about this if you try using it on a local account, and then shut itself down.
- Windows 10 start menu will have "Content suggestions" which are on by default, which means you'll be seeing ads.
- Windows 10 "Wifi Sense" will be begging for your Facebook account details so it can get to know you better.
It will also be sharing your Wifi password with all your Facebook/Skype/Outlook friends, their friends, as well as Microsoft.