Android: ProgressDialog.show() crashes with getApplicationContext

I can't seem to grasp why this is happening. This code:

mProgressDialog = ProgressDialog.show(this, "", getString(R.string.loading), true);

works just fine. However, this code:

mProgressDialog = ProgressDialog.show(getApplicationContext(), "", getString(R.string.loading), true);

throws the following exception:

W/WindowManager(  569): Attempted to add window with non-application token WindowToken{438bee58 token=null}.  Aborting.
D/AndroidRuntime( 2049): Shutting down VM
W/dalvikvm( 2049): threadid=3: thread exiting with uncaught exception (group=0x4001aa28)
E/AndroidRuntime( 2049): Uncaught handler: thread main exiting due to uncaught exception
E/AndroidRuntime( 2049): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.tastekid.TasteKid/com.tastekid.TasteKid.YouTube}: android.view.WindowManager$BadTokenException: Unable to add window -- token null is not for an application
E/AndroidRuntime( 2049):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2401)
E/AndroidRuntime( 2049):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2417)
E/AndroidRuntime( 2049):    at android.app.ActivityThread.access$2100(ActivityThread.java:116)
E/AndroidRuntime( 2049):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794)
E/AndroidRuntime( 2049):    at android.os.Handler.dispatchMessage(Handler.java:99)
E/AndroidRuntime( 2049):    at android.os.Looper.loop(Looper.java:123)
E/AndroidRuntime( 2049):    at android.app.ActivityThread.main(ActivityThread.java:4203)
E/AndroidRuntime( 2049):    at java.lang.reflect.Method.invokeNative(Native Method)
E/AndroidRuntime( 2049):    at java.lang.reflect.Method.invoke(Method.java:521)
E/AndroidRuntime( 2049):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)
E/AndroidRuntime( 2049):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.ja