How To: Remove White Dots From LightDM Greeter On Ubuntu 11.10
Here is a guide to remove the white dots from the login screen (LightDM greeter) on Ubuntu 11.10. You can remove the dots by upgrading the default lightdm package for a modified one. The lightdm greeter is modified by Scot Severance, he removed the white dots and to keep it simple to install he also created a PPA for an easy install.
To add the PPA and upgrade the LightDM greeter open a terminal window (press SuperKey and type: terminal) and copy+paste the following lines:
sudo add-apt-repository ppa:scott.severance/lightdm
sudo apt-get update
sudo apt-get upgrade
When done close your terminal window and logout to see a nice login screen without the white dots. If you want to change the background and/or remove the Ubuntu logo you can use the simple lightdm manager.