"Amy" hit XBOX Live yesterday. From what I've seen, it's an entire game built around an escort mission where you have to protect a little girl. Mixing stealth with limited, "realistic" combat, all wrapped in a survival horror game's clothing. At only 800 points it might be worth it? On the other hand, I can't think of one time ever when I enjoyed an escort mission, or little children in a game... so, there's that.
Here's an interesting video highlighting the gameplay. I'm a little intrigued by the stealth aspects. If you play it, be sure to chime in and let us know.