I get the following exception when trying to use the Google Play Services V2 library after following the official tutorial.
java.lang.NoClassDefFoundError: c
Version 2 includes resources and must be imported as a library project. See the instructions at http://developer.android.com/google/play-services/setup.html for how to do that in various IDEs.
The resources are for GooglePlayServicesUtil.getErrorDialog(), which directs the user to install, update, enable, etc. Google Play services if it isn't available on the device.