Version 4.1 of the Linux kernel was released this week, and it includes a number of new features in the following areas.

Power Management

Several power-saving features have been integrated into the kernel, and the majority of them target high-end Intel chips. The improvements consist of tweaks to improve performance and reduce power consumption, and early reports claim they can help extend battery life by up to an hour.

EXT4 Encryption

It's now possible to encrypt EXT4 filesystems, thanks to code contributed by Google. The code originally was developed for Android and has been pushed up-line to the mainstream kernel. This will be interesting news to government contractors and others who work in secure environments, where filesystem-level encryption is mandated.

Graphics

Version 4.1 includes improvements that effect several GPUs, including the GeForce GTX series. NVIDIA enjoys a troubled relationship with Linux, to which many users and developers will attest, and the company's unwillingness to release open-source driver code has created a lot of problems for the kernel team. Linus has been quite vocal on the subject. Here's a brief summary of his views on the subject (contains cursing): https://www.youtube.com/watch?v=iYWzMvlj2RQ.

The new version includes improvements that make it easier to configure Nouveau for the GeForce GTX 750. In the past, the process involved the manual extraction of firmware blobs, which is exactly as painful as it sounds.

Intel GPU support in virtual machines had been a bit troublesome in the past, but Linux 4.1 now supports XenGT vGPU for use with the Intel Xen hypervisor. A version for KVM is in the works too.

Version 4.1 also supports DisplayPort MST for Radeon cards.

Better Laptop Support

Updates to the Atmel MXT driver mean that the touchscreen and touchpad of Google's Pixel 2 Chromebook are now fully supported.

Linux 4.1 also now can control the keyboard backlights on Dell laptops, which is great news for midnight typists!

The updated Toshiba ACPI driver now supports a host of fancy features, including adaptive keyboard buttons, USB sleep and charge, hotkeys, keyboard backlighting and more.

Game Support

X-Box One controllers gain force feedback and rumbler support in kernel version 4.1.

These changes are just the highlights; there are tons of other entries in the change logs.

Currently, 4.1 has not yet made it into the repos of the major distributions. That's understandable, as it's only just been released, but it's only a matter of time until it is included. For instance, Ubuntu will start supporting it in October 2015. If you want to start using it before then, you can install it from a custom repository (as provided by the community), or compile it from source.