More of what appear to be placeholder particle effects associated with grenade explosions. In the background, you can see a blue spartan charging the spartan laser, indicated by the bright red spot.

Here we see a spartan preparing to jump off an object that is speculated to be something akin to a portable mancannon; an air lift similar to those found in Halo 2's multiplayer levels Warlock and Foundation, but in a piece of equipment that can be carried and deployed by a player.

Such equipment would appear to be one of Halo 3's major changes, compared to the previous games. At least two pieces of equipment are shown in the video and specifically referred to: the bubble shield (as seen in the "Starry Sky" CGTV ad from late 2006) and the tripmine, shown later in the VIDOC.

Frankie's post in the NeoGAF forum indicates there are an unspecified number of additional pieces of equipment; the air lift shown here may be one of them.

Interface designer David "Evil Otto" Candland, shown with what appears to be Halo 3's medals. Some are familiar (assassination, beatdown, sticky, snipe, doublekill) but some appear to be new.

Bungie's Frankie was very clear that this VIDOC contains graphics that are from the Halo 3 alpha-- they're not what the public beta will look like, and they're not what the released game will look like. Some of the simplified particle effects, such as this grenade explosion and others seen throughout the video, seem to support this.

Secondary weapons are now visible, slung on the back of the Spartan model. This one, armed with an assault rifle and carrying a brute shot as a backup, looks like he's wearing a sombrero.

Tyson "Ferrex" Green, Multiplayer Design Lead, in his trademark "fishin' bob" hat and sporting a trust-evoking t-shirt. We do, rex... we do.

Early in the documentary, two blue spartans concentrate AR fire on a red opponent similarly armed.