So upstart-udev-bridge is a transitional software package to start things up until init gains the ability to do so for itself.
udev deals with starting up devices, it has been known to relate to cdroms, and other hardware devices presumably.
I learned that you can "monitor it" using udevadm monitor.
Here is what I found:
udevadm monitor
monitor will print the received events for:
UDEV - the event which udev sends out after rule processing
KERNEL - the kernel uevent
KERNEL[1309201501.345628] change /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0C0A:00/power_supply/BAT0 (power_supply)
UDEV [1309201501.346393] change /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0C0A:00/power_supply/BAT0 (power_supply)
KERNEL[1309201502.364125] change /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0C0A:00/power_supply/BAT0 (power_supply)
UDEV [1309201502.365439] change /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0C0A:00/power_supply/BAT0 (power_supply)
...repeat forever.
So it's checking for my battery, which somehow one day decided that it wasn't going to be recognized any more. Since a battery is a nice thing to have, I think that it checks on a frequent basis when it can't find one on the laptop.
Sooo, it seems to be a hardware problem that may be resolved when I obtain a working battery for this laptop.
/var/log/syslog
? Is your disk healthy? (see Palimpsest Disk Utility - SMART data)