The "Lumia Denim" update, which is rolling out today, actually takes users straight to Windows Phone 8.1.1, skipping over last summer's "Lumia Cyan" update that Verizon never delivered.
That means users are getting a major overhaul as part of Windows Phone 8.1, with features like Cortana, Action Center for notifications, the Word Flow gesture keyboard, greater Start screen customization, and improvements to core apps. (Check out our full rundown of Windows Phone 8.1 features for more details.)
A further update to Windows Phone 8.1.1 adds Start screen folders and VPN support. Cyan and Denim also include some enhancements specific to Lumia devices, such as better camera performance and responsiveness, improved audio quality in videos, continuous auto focus and 4K video capture.
Microsoft says the update starts rolling out today, and you can check for it by going to Settings > Phone Update > Check for Updates. If you're too impatient to wait for the update to hit your phone over-the-air, Paul Thurrott has instructions on how to install it right away, but keep in mind this method will erase the contents of your phone.
The story behind the story: Microsoft has occasionally struggled with wireless carriers to deliver updates in a timely manner, and as a Verizon flagship, the Lumia Icon is one of the worst examples. While Microsoft has offered a workaround in the form of a " Preview for Developers," going this route can cause bugs and denies users of new Lumia-specific features. With Windows 10 looming, Denim users can only breathe a temporary sigh of relief that their devices are up to date.