I am not sure if its a bug in my .13 install to the n810 or not, but since its happened three times, here's the report:

Simply speaking: I lock the device and come back the next morning with the battery dead. It is not connected to any network, nor is there any apps running other than what runs from the opening boot.

I have this installed on the internal memory, using internal memory as swap. This was an overwrite of the .12 version, and there was an interruption of the install to .13 when initially installed.

Hope that helps recreate and nail the issue if Mer is the issue.