As of this week on 13 January 2015, Microsoft’s Windows 7 finally entered into extended support and will continue to receive critical support for a number of years, up to 14 February 2020. What this means, really, is that it’s definite confirmation that DirectX 12 won’t come to Windows 7, because any product in extended support won’t receive new features or capabilities. If you’re keen on DirectX 12, you may want to jump to Windows 8.1 or save up some cash for Wind0ws 10.
Otherwise, there’s really not much wrong with Windows 7 at all, so those of you choosing to stick to the platform can rest assured that it’ll see another five years of solid support before it becomes necessary to upgrade. Keep in mind, also, that Vista’s extended support for Service Pack 3 ends on 11 April 2017, so you’d better hurry off that platform asap.
Source: Microsoft Support