It is reported to be mostly performance-enhancing and brings no visual changes. If you own a Symbian^3 smartphone, launch the Software Update app on your phone to see if the update is available for you yet.
My N8 is already running Belle, so I am wondering if I will get this? So far, the update app tells me my N8-00 is already fully up-to-date.
Do let us know when you get the update on your phones and share if you notice any difference in performance.