New CPU architectures require new OS kernels to take advantage of the new features.
That is probably why Win7 isn't officially supported on the Skylake platform.
I have the 1511 Win10 update installed. There are some nice features and polish to the GUI.
It's hard to tell if its faster, as I currently have an Samsung 950 Pro NVMe SSD running the OS. Before the 1511 update the OS was running from an 850 Pro SATA SSD.
It is noticeably faster, but that could just be down to the NVMe SSDs higher performance and much lower latency when compared to SATA.