I was affected by this issue as well. That is, I upgraded from natty to oneiric release and upon reboot no X server started. The last message on the console was "Checking battery state", but I expect that's just the last init script that ran and unrelated to this issue. The problem was that no DM was starting even though I could start both lightdm & gdm manually.
After reading the comments in this bug, I ran "dpkg-reconfigure lightdm" and chose lightdm as my DM. This resolved my issue with no other steps required. Fwiw, I was not prompted to choose a DM by the release upgrade process.
I was affected by this issue as well. That is, I upgraded from natty to oneiric release and upon reboot no X server started. The last message on the console was "Checking battery state", but I expect that's just the last init script that ran and unrelated to this issue. The problem was that no DM was starting even though I could start both lightdm & gdm manually.
After reading the comments in this bug, I ran "dpkg-reconfigure lightdm" and chose lightdm as my DM. This resolved my issue with no other steps required. Fwiw, I was not prompted to choose a DM by the release upgrade process.