I think this post has a much better solution for modern Ubuntu (10.X):
... booting with the text kernel parameter will also prevent display managers managed by Upstart (e.g. gdm, kdm and lxdm) from being started at boot time.
If you are using Grub2, then in
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash text"
splash to disable the splash screen and/or
quiet to make the boot process verbose. If you wish to create a separate boot option for the text and GUI mode then check out this.
Then, if you want to go graphical after booting up, I guess you can use