I think I'll hold off upgrading to 10 until it's closer to being finished. Right now, it shouldn't have left beta.
Still, on the plus side, it'll probably be lucrative for IT techs when non-contract clients brick their machines with failed updates, or when machines with unsupported graphics cards get updated.
GWX notification can be easily disabled by uninstalling and hiding KB3035583, editing registry, enabling Group Policy, etc. When a user cannot do this, it only means they need OS managed and updated for them automatically, it's just better for everyone involved.
I noticed a couple of days ago that KB3035583 (plus another annoying Win10-related update), which I had hidden a while back, got unhidden and presented to me again for installation. You need to constantly review the list of updates in each batch of updates to keep Microsoft from tricking you into re-installing it! They just won't take "no" for an answer. (I'm on Windows 7 and have no intention of ever "upgrading" to Win10. My upgrade path will probably be Linux.)
I saw a comment elsewhere that stated in the win/sys32/gwx path to create a 0 byte gwx.exe which I believe has helped with disabling the notification as well.
It is really bothering. I want to stay on win 7 as I don't want to give my email to get further updates or to use cortana. I don't know of a way to avoid the nagging reminder... sucks.
Instructions are here: http://www.myce.com/news/how-to-uninstall-kb3035583-the-wind...