Starting from today Pharo 3.0 includes Metacello2.
Beside many improvements you can now also make your project configuration class (which usually is named after your project "ConfigurationOfProjectName") a subclass of the predefined class ConfigurationOf.
ConfigurationOf subclass: #ConfigurationOfExample
So no need to include metacello bootstrap methods on each configuration.
Did I mention that you can now also work with FileTree and GitHub? ;)