No answer yet.

No answer yet.

The word so far seems to be that the Arbiter will accompany the Chief on certain missions; as such, it may be assumed that he is invulnerable, or else he may disappear from the game before completion.

Other NPCs that accompany the player through the game will not be invincible.

No answer yet.

Preliminary media, such as screenshots released on Bungie.net and in major magazines such as EGM, as well as the "Et Tu, Brute?" video documentary released on XBL and Bungie.net, have shown several new weapons. Spartan Laser An anti-vehicle weapon of high power and long distance, but with long recharge time and limited ammunition. Spiker (or Spike Rifle) Apparently the default weapon for Brutes, something along the lines of the Elites' standard plasma rifle or the marines' SMG. Very likely a replacement for the red Brute plasma rifle.

There are indications that although dual wielding will return in Halo 3, there will be somewhat less emphasis on it.

Bungie's public comments about Halo 3's weapons so far do not provide a complete answer to this. Their weapon balance philosophy, though, can be seen in their comments about the revised assault rifle, a weapon created to be a default spawn gun with medium range, decent accuracy, not capable of headshots, and not dual-wieldable. Its ammunition capacity will be somewhere between the copious amounts the original assault rifle held, and the relatively meager capacity of the battle rifle.

Halo 3's methods for handling grenades and grenade limits will likely change due to the introduction of the Spike Grenade, and the reduction in the number of grenades of each type that can be held from 4 to 2. However, indications are that multiplayer game types will be even more customizable in Halo 3 than they were in Halo 2, so although there is no explicit mention of it, it is conceivable that there might be an option for unlimited grenades of one or more types in a multiplayer game.

Early screenshots of Halo 3 multiplayer action, such as the attached, have shown vehicle boarding. While all features are subject to change prior to release, it's probably a good bet Halo 3 will still have this popular feature.

According to Bungie, the release dates of the game and the film "will not affect each other." Source: Halo Weekly Update 05132006

According to Bungie's director of cinematics, CJ Cowan, texture pop "has already gone bye-bye" in Halo 3. Source: Halo Weekly Update 05132006

Again, Bungie has said nothing yet, but here's hoping they change things. Speech in Halo 2, in my opinion, doesn't work terribly well. Enemies can always hear you within a given radius, even through structures, while the interface requires you to specifically signal that you want to communicate to remote teammates-- and even when you do so, nearby enemies can still overhear you.