now. the point of this is to give an educated guess as to why bungie would put brutes into there next game, halo reach. i am not here to say "OMG iS th3re h4s to be br00t5 in R3ach 0r is n0T GOnn B3 br00ts in rach!" i am tryin to explain my reasoning as to why i believe that not only will we be able to play as brutes in multiplayer but campaign too. my first point will be looking at the timeline of the halo multiplayer and campaigns of the past games.
halo 1: in halo 1, you only played as a spartan in multiplayer and in campaign. the only way you could change your armor is by changing your armor color.
halo 2: in halo 2, bungie decided to add another race to the picture. you could now play as elites, the covenants most infamous warrior. however, they not only added the elites to multiplayer, but to campaign in order to explain the covenant's side of the story and how they became seperatists. elites did not have any advantages or disadvantages from the spartans.
halo 3: in halo 3, bungie decided to broaden the armor spectrum again by adding permutations. permutations allowed you to choose from multiple layouts of spartan and elite armor. these permutations had no effect on the hitbox. it is rumored that bungie was going to add brutes to the multiplayer experience, but was unable to due to time restrictions.
halo reach: as you see, bungie has added new armor to each game and that is why bungie will add either more armor permutations or an entire new race to multiplayer. if they just added new armor permutations it would seem as though they are being repetitive and too much of a copy and paste job. if they added brutes they would also probably make at least 1 campaign mission where you play as them because in every game with elites in them, you were able to play as elites in campaign. my guess is that playing as brutes will lead some backstory into why they are attacking reach and what they think is here. maybe a legendary ending will reveal something new we don't know about reach.
brutes on reach?: there is no definitive proof that brutes were or were not on reach. some people have stated that the prophets did not want the brutes because they were to careless and would destroy some of the sacred items on reach. if they weren't on reach it is possible that they were above reach in some of the covenant cruisers. maybe one or more of the missions will be a covenant cruiser invading a unsc cruiser, and will be played through the eyes of a brute.
=>these are only opinions, and are meant to be treated as opinions, please do not treat me as though i am a fool telling bungie what to do, and please no flaming<=