First things first!! Big thanks to our sources for providing us with correct information about Lumia Cyan update roll-out timings. This made us to post about the Lumia Cyan update timings exclusively!!
Anyways, now coming to what changes will be seen on your device post Lumia Cyan update, no better place to get it all, than our Lumia Cyan and Windows Phone 8.1 dedicated page. It is most comprehensive coverage on the web.
In case you want to check when the update will be available for your device, you can use the official Lumia Cyan roll-out tracker. Though our past experience tells us that you may get the update before it appears on that page. Currently the Lumia Cyan update for all the devices in all the regions is mentioned as “under testing”. Stay tuned to NPU, as we will keep you updated.
Here is the official Lumia Cyan hands-on video,