The new voice-activated Google Mobile app for the iPhone is finally here. Whatever the reason for the delay, it was worth the wait. As we wrote last week, the search app knows when you bring the phone to your face to speak into it. It beeps, you talk, and it executes a Google search on what you said. (If you're using a headset, you have to press a button. You can type in your queries, too, if you want.)