Flash and a Lesson on Backports

I've grown tired of looking at the default GNOME theme, which to me is really ugly. As I was researching themes I got tired of looking at broken flash content too, so I installed the flash plugin package. This package is a backport, so you will need to edit the /etc/apt/sources.list text file in order to add backport packages. Less than a week in, and I've already sullied my pure "stable" installation.

Here's the process:

vim /etc/apt/sources.list

Add the lines:
deb http://www.backports.org/debian main contrib non-free
deb-src http://www.backports.org/debian main contrib non-free

Now add "contrib non-free" to the other lines as well.
ie: "deb http://ftp.us.debian.org/debian lenny main contrib non-free"

Then you have to update the package list, install the keyring package to authenticate downloaded backport packages, and install the plugin package. Here are the commands:

apt-get update
apt-get install debian-backports-keyring
apt-get install flashplugin-nonfree