After you update the SDK tools(r7) from the Android SDK manager or otherwise, you would be prompted to update the ADT plugin(0.9.8) as well. Go for it, and you will see quite a few changes.
In the SDK Tools:
In the ADT Plugin:
For SDK Tools
- Support for library projects.
- Support for aidl files in library projects
- Support for extension targets in Ant build to perform tasks between the normal tasks
- Support for "headless" SDK update
- Fixes location control in DDMS to work in any locale not using '.' as a decimal point
For ADT Plugin
- Rename package : One click change of project's package
- Support for library projects that don't have a source folder called
-Support for library projects that depend on other library projects
-Support for additional resource qualifiers:
-Adds more device screen types in the layout editor. (Nice)
-Fixes problems with handling of library project names
The most important update for me is the inclusion of more layout editor configurations by default. My last post on creating different configurations for different screen sizes here was just an example to create a configuration for working with different screen sizes at design time. It's a bonus that they are now included in there by default.
Once click package renaming is also a nice feature, in case you want to fork your project into different versions. Check them out.