Android GCM basic implementation

UPDATE: I fixed the problems in the code below so this makes a nice basic working example of how to use GCM

So, I'm trying to implement Android GCM into my app. Here are the relevant parts I've added to the manifest:

<uses-sdk android:minSdkVersion="8" android:targetSdkVersion="20" />

<permission
    android:name=".permission.C2D_MESSAGE"
    android:protectionLevel="signature" />
<uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />
<uses-permission android:name=".permission.C2D_MESSAGE" />
<uses-permission android:name="android.permission.WAKE_LOCK"/>
<uses-permission android:name="android.permission.GET_ACCOUNTS"/>

...

<receiver
    android:name="com.google.android.gcm.GCMBroadcastReceiver"
    android:permission="com.google.android.c2dm.permission.SEND" >
    <intent-filter>
        <action android:name="com.google.android.c2dm.intent.RECEIVE" />
        <action android:name="com.google.android.c2dm.intent.REGISTRATION" />
        <category android:name="com.badbob.app.gmctestapp" />
    </intent-filter>
</receiver>

<service android:name=".GCMIntentService" />

I've added the following code to the onCreate of my main activity:

    GCMRegistrar.checkDevice( this );
    GCMRegistrar.checkManifest( this );
    final String regId = GCMRegistrar.getRegistrationId( this );
    if( regId.equals( "" ) ) {
        GCMRegistrar.register( this, GCM_SENDER_ID );
    }
    else {
        Log.v( LOG_TAG, "Already registered" );
    }

I've also created the GCMIntenetService class like so:

public class GCMIntentService extends GCMBaseIntentService {

    private static final String LOG_TAG = "GetAClue::GCMIntentService";

    public GCMIntentService() {
        super( GCM_SENDER_ID )