Today the Dev-Team found that the SHAtter exploit can actually the Apple TV 2G into restoring a pre-jailbroken IPSW.
This was confirmed with an update to one of their recent posts:
UPDATE #2: It‚Äôs confirmed‚Ä¶SHAtter can trick Apple‚Äôs new AppleTV 2G into restoring to a pre-jailbroken IPSW from PwnageTool too! Literally the only UI application on the ATV is Lowtide.app, but now the window is open for jailbroken apps of all varieties. (Just like the early iPhone days, the only apps you‚Äôll see on the AppleTV will be jailbroken ones). In the meantime, here‚Äôs a video showing root access (via ssh) into Apple‚Äôs new product.
See, the UI in Apple TV 2G is essentially an App called Lowtide running in iOS. It's the only App the box is designed to run. However, they were able to kill the App and open the custom IPSW. This may indicate that in the future you should be able to run JB Apps on Apple TV.
Here's some related information where you will even see a user get Lowtide to run an iPod Touch: Apple TV Will be Very Hack-Friendly