I've had this issue on multiple ubuntu based distros, the most recent being elementaryOS Luna.
Basically, I keep my laptop plugged into a 1280x1024 monitor at home. Whenever my laptop is powered off and the monitor is unplugged (for example, when I take it to class in the morning and it is already off) I am not presented with a login screen. I can see the POST screen as well as the boot-splash, but then the screen goes blank (but the backlight remains on).
Is there another fix other than simply adjusting my display configuration before shutting down? My laptop has a 2nd gen i3 in it and no other graphics card.
EDIT: I should add that even with the monitor connected, I can no longer see any login screen or switch to any VT. This happened before on a different distro, and I had to re-image my linux partition.