Microsoft has a complicated new plan to add new features to Windows 10 and make money

Microsoft keeps dropping hints about how radically different Windows 10 will be from all other versions of Windows like a trail of breadcrumbs leading to no-one-fully-knows-where yet.

And now we have another clue, from ZDNet's Mary Jo Foley, which adds details to the information we reported in March about Microsoft's plans.

Microsoft is creating a complex matrix of support options for Windows 10, she reports, and it will charge for them in an increasingly complex way, allowing it to continue to make money on Windows, even if a lot of people opt for the "free" upgrade to Windows 10.

With Windows 10, only the biggest enterprises will get full control over installing updates, Foley's contacts tell her. Those customers will generally be paying for Windows. As Business Insider previously reported, we're also hearing that big enterprises will also get a menu of support options, each at different prices.

Most Windows users, including consumers who get the free upgrade, will not be able to turn automatic updates off.

The key phrase Microsoft keeps using is "Windows as a Service."

Microsoft hasn't fully explained what that means except for calling Windows 10 "the last version of Windows" and indicating that Microsoft will automatically send new features and security patches through its new and improved Windows Update service. And Microsoft declined comment when we reached about.

The issue is how much power a user gets over which features and security patches get installed and when. Foley's contact calls these options "servicing branches."

Different versions of Windows (for consumers, businesses, and large enterprises) will be members of different branches.

Windows 10 Home, for instance, will be part of something called the "Current branch" which means Microsoft will send updates and you won't be able to refuse them or turn them off.

The enterprise branch will have a lot of control.

Sending updates like this isn't a bad thing, and many consumers will be happy to get the latest features and security fixes.

But there's a legitimate reason to be concerned over how intrusive such updates will be - for instance, if they automatically install while you're in the middle of an important task, sucking up memory or forcing your computer to reboot - and if they'll always play well with other software and drives you have installed on your PC.

For enterprises, cost is also a concern.

A person previously told us, "Windows and Office are about to get much, much more complex, confusing, and expensive in the coming years when Windows and Office become 'freemium' with 'added value' bundles sold on top of the platforms."