I've contacted the Product Manager who will reply to this question. He's currently at VMworld so we should expect a delay in his response.
So, we do need to actually see the October updates before we will know for sure, but here is what I know right now.
- There will be options to do the Cumulative Rollup, which is the Windows 10 equivalent, but there will also be an option to do a security only bundle each month.
- OS and IE will be in the Cumulative Rollup and Security Only bundle. .Net will be a separate rollup. (so to your question about the patch groups, you would be able to choose between those three things)
- I expect we will flag the CR as non-secuirty and the security only as the security update each month and the .Net patch as a security patch as well.
- There was no mention of Office, SharePoint, SQL and other solutions as being part of this, so assume these are to be separate updates for the time being.
Take this with a grain of salt for now, as there are some speculation and assumptions based off of the available facts. We will know more by October Patch Tuesday. I plan to spend a good chunk of time on this in my October Patch Tuesday webinar. Hit the Patch Tuesday page to sign up for that or watch the blog for more detail as October hits and things unfold. www.shavlik.com\patch-tuesday