Don't reward this behavior by buying Windows 10. Or at least delay the purchase as long as possible.
That's like you know there's a hissing cockroach living under the sink but you just close the door and stick your fingers in your ears.
This is because Microsoft will release "updates" to that package, with the totally unintended side effect of unhiding and reinstalling the update. So even if you uninstall it, and hide the update from WU, it will still find a way onto your system.
So yeah, like I said and despite the downvotes, it's fucking adware. Bordering on malware.
(Actually I did a brief search, and didn't find anything.)
So at this point, maybe you're right and it's not adware. I'd consider it borderline at least, but fine. Whatever.
However I got a second notification some weeks later, from the same package which I had already uninstalled and hidden remember, after it apparently reinstalled itself because MS released an 'update' to this package. So despite uninstalling it and following all the steps required to clearly communicate that no, I do not want this fucking thing on my PC, MS decided they'd push the update to my system anyway.
At this point it's no longer borderline. It is harassing behavior from something that is very obviously adware.
Because Linux distributions like Ubuntu never ever encourage you to upgrade your system to the newest and shiniest version, right?
Oh, I wish what you said was true. It's funny because they didn't do that when I was on an older version of Ubuntu (11? 12? I forget). It just kept popping up and telling me to update no matter what I did. Stuff like this: http://askubuntu.com/q/218755
There's no buying if you've already got a valid Windows 7/8 license; it's a free upgrade. And as long as it's optional, I don't mind this instance of a notification for a very generous offer (at least generous in terms of regular Microsoft pricing).