We have just released new versions 1.2.0-J5 and 1.2.0-J6. As usual, they are functionally equivalent, the first for JIRA 5.X and the second for JIRA 6.X.
The main new feature is the ability to export all projects in an instance to a single XML file. Also the loader is able now to import in a single operation a file with configuration for more than one project. Obviously, you should take into account that the time needed to export and import a file with configurations for many projects will be longer, so maybe you will have to wait a bit for your browser to display the result.
This version also includes support for ordering of issue types within an issue type scheme. Previous versions did not take it into account. It also fixes the problem described in this question at Atlassian Answers.
The plugin keeps compatibility with the previous XML file format, so you can still load files exported by previous versions. There is a minor exception related to a specific post-function defined in Script Runner plugin, that hopefully will affect very few users if any. If you are interested in knowing more about it and how to make the file load in the new version have a look here.