Firecore has updated Seas0nPass to support a tethered jailbreak of the new Apple TV 4.2 (iOS 4.3) software. Seas0nPass allows you to jailbreak your atv2 with the latest 4.2 software by creating custom Apple TV IPSW files and restoring them in iTunes (similar to the existing Pwnage Tool app). It also includes a simple ‘tethered boot’ option.
aTV Flash black
Fire Core has finally released the first beta version of aTV Flash (black) for the Apple TV 2G. It gives you a web browser with HTML5 support (not all HTML5 sites are supported yet), a Plex client that lets you stream nearly any kind of video from Plex Server running on your Mac, Last.fm access and some info on demand (current weather and news feeds). Fire Core promises to enable additional media formats such as AVI, MP4, MKV, DVD files and to support media streaming from most NAS devices (including Airport Extreme and Time Capsule) in the near future. You don’t need to be worry about the original Apple TV features, they will all remain fully operational.