PRE-DOWNLOAD WORD OF WARNING, READ!
Before you continue to the download page, make sure you've read the following blog posts as these are really important in understanding the latest additions to the Viewer and how they work.
Remappable Keys Update 1 and Update 2 -- RECOMMENDED
Screen Space Ambient Occlusion (SSAO) Overhaul
Avatar Rendering Complexity (Jellybabies) Introduction -- RECOMMENDED
Chromium Embedded Framework (CEF) Introduction
Viewer Managed Marketplace (VMM) Introduction
Unified Notification Console Introduction
Windows 10 Support
Unified Snapshot Floater Enhancements
If you've read and understood which features were added, changed or removed and you are aware of their quirks and all important information about privacy, you may proceed to download the Viewer below but be warned that reporting issues or "bugs" that are no bugs but rather features as explained in the above blogposts, you might not experience the nice attitude you may expect. I warned you. Proceed to download the Viewer here.
This software is not provided or supported by Linden Lab, the makers of Second Life.