Nokia has now moved on to Windows Phone mobile platform though they continue to sell Symbian based devices.
Symbian development is now handled by Accenture. And we now have some leaked updates on the future.
Online reports say that after Anna and Belle we are now going to see Donna and Carla updates to Symbian in the future.
These updates could be reserved for dual core smartphones so current generation devices are likely to be stuck with Belle.
The reports said that Symbian Carla update could bring support for Dolby Surround Sound, NFC functionality, much improved web browser in addition to improved widgets. Donna is of course too far away right now.