I am having issues with the latest OS update on my N800 as well. In my case, after downloading and installing the update, the tablet never rebooted. I had to use the hardware keys to turn off the device and back on again. Now control panel does show the updated version - however since I have upgraded, I am noticing that the tablet display is behaving strangely. Often times , when i have left it on for a few minutes, and the screen has gone blank, when I tap on the screen, the screen does not come back to life. I can hear it launching programs ( depending on where I tap ) , but no display ! This happens even with a full battery. If I somehow manage to turn it off using the hardware keys, next time I turn it on, sometimes it will work, and other times the problem will persist ( i.e. the tablet boots, but no display )

I have tried taking the battery out and putting it back on, but that has not solved the problem. Also as I mentioned, there is no pattern to the problem. It happens sometimes, and other times works just fine.

Anyone else facing similar issues and has found a solution ?