Can I disable the Ubuntu splashscreen?

Edit grub, paste this at a terminal: gksu gedit /etc/default/grub

Look for the line

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

and change it to

GRUB_CMDLINE_LINUX_DEFAULT=""

save.

Then at terminal paste this:

sudo update-grub

I've been working on this exact problem all day...
Ubuntu Server 12.04.03 LTS amd64 on a dual NIC, dual core Intel Atom with the N2000 graphics chipset. Had to blacklist the gma500_gfx driver to get video at all, and then on to seeing the boot up...

Editing the kernel parameters in /etc/default/grub to:
GRUB_CMDLINE_LINUX_DEFAULT=""
did not work for me. The splash screen went away but the screen stayed blank.

Adding this to /etc/default/grub worked for me:
GRUB_GFXPAYLOAD_LINUX=text