Today Nokia released a new firmware version 81.004 for its business series smartphone E5. Software version date is 22nd October 2011.
I have upgraded the firmware over the air (OTA) today itself.
There is no "what's new" type information available on the internet yet. Neither I have come across any release notes.
I haven't noticed any new features yet. So there might be only bug fixes in this upgrade. The user interface seems to be a bit faster than what it was earlier. But that can just be a perception.
I will post if I notice any new feature which I might have missed out.