Hey, I was having the same problem with my intel 945GM (i915) on my Gentoo system. Here's how I solved it.
This <https://bugs.launchpad.net/ubuntu/+source/linux/+bug/515246/comments/7> just gave me the hint to look for the 'video=LVDS-1' option, which pointed me to Intel's documentation at <http://intellinuxgraphics.org/documentation.html>.
The problem: your BIOS, like mine, is mistakenly reporting the laptop lid as 'closed', so the i915 KMS driver turns off the display. Starting in kernel 2.6.32, the kernel folks just decided they should start listening to your BIOS in this regard, and that's why it's all messed up now.
The WRONG solution (only useful if everything else fails, because it will render your suspend/hibernate useless): use 'acpi=off' in your kernel line in Grub.
The RIGHT SOLUTION: use 'video=LVDS-1:e' in your kernel line in Grub:
1- edit /boot/grub/menu.lst
2- find the line beginning with 'kernel (hd0,...
3- append this to that line:
4- It should work now like it used to.
Please tell me if it works for you, too.