As of October 2016, Windows will releasing single monthly rollups that will contain both security issues and reliability issues in the single update for most Windows operating systems. The monthly rollup will be released the usual ways but not through the download center. Each month’s rollup will supersede the previous month’s rollup. So to be current, you just need the latest rollup.
Over time, Windows will also add patches released in the past to the monthly rollup. Eventually all of the patches Microsoft will be included since the last baseline [unsure at this time what the baseline is] and the monthly rollup will become a fully cumulative update. They are unsure how IE will be included as multiple versions of IE are supported. Flash Player and servicing stack and some specialty updates are not included in the rollups.
As well, from October 2016 onwards, Windows will release a single security-only update which will collect all of the security patches for that month into a single update. But unlike the monthly rollup, the security-only update will only include new security patches that are released for that month. So at one point you will have 12 related security updates per year plus the latest cumulative update plus an IE update, a Flash update [Windows 8.1 only] and any specialized updates. Nothing else.
The .NET Framework updates will also follow the monthly rollup model with a monthly release that will be known as the .NET Framework Monthly Rollup. This monthly .NET Framework Monthly Rollup will deliver both security and non-security updates to all versions of the .NET Framework as a single monthly update. The Monthly Rollup will not automatically upgrade the base version of the .NET Framework that is installed. A separate security-only update on Microsoft Update Catalog and Windows Server Update Services every month.
Finally, the Microsoft Update Catalog website will be updated to remove the ActiveX requirement so it can work with any browser [it doesn’t work properly with Microsoft’s own Edge!]. Microsoft is expected to launch the updated site soon.
The news applies to Windows 7, Windows 8.1, Server 2008 R2, Server 2012 and Server 2012 R2. As support for Vista and Server 2008 dies next year, they aren’t bothering to follow this schedule. Few reliability [non-security] updates are released for Vista and Server 2008 anyways.