I was reading about the release of Chromium for the Raspberry Pi and read a comment about changing the memory split using rpi-update. I decided to see what it was all about.
RPi-Update makes it much easier to change the memory split and keeping the firmware up to date rather than doing it manually. You can find it here
Here is how I ended up getting it to install without the errors I got. This is based on the Debian Squeeze release from 06-19-2012. I haven't switched to Wheezy yet.
sudo apt-get install ca-certificates
sudo apt-get install git-core
sudo wget http://goo.gl/1BOfJ -O /usr/bin/rpi-update && chmod +x /usr/bin/rpi-update
If you get a error about the library then (I can't remember the exact message)
Then you can set the memory split. I used
sudo rpi-update 224
since I am not using the GUI.