Major refactoring of the core classes were made for this release (some breaking changes) . Castle's IoC container is now used to resolve dependencies and the functionality (which is mostly the same) has been splitted into smaller classes.

If you've been using v1.1.x you will need to update configuration, change calls to the rewriter class and probably some other things as well. Look at history.txt for a longer list of changes and at upgrade.txt for help upgrading.