The Halo Legends won't be out for months. Spike will be airing up to seven minutes of it tonight. The shot above is clipped from that clip.
Spike's Halo 3 ODST Countdown To Launch special airs at midnight tonight, Eastern and Pacific, featuring host Geoff Keighley and a trio of Halo-minded experts, Bungie's Joe Staten and Brian Jarrard along with 343 Industries' Frank O'Connor. They get a Keighley grilling about all things Halo.
Possibly more exciting for Halo fans will be the debut of several minutes of action from the Halo Legends anime, focusing on the "Babysitter" short. The clips I've seen have a Spartans and ODSTs in action, snapping at least one neck and delivering the most viscous punch I've ever seen in a Halo project.