Agreed, I haven't read Cryptum or Primordium but I know enough about them. The description also hints at it.
"Set in the aftermath of Halo 3, Master Chief returns to confront his own destiny and face an ancient evil that threatens the fate of the entire universe. Halo 4 marks the start of a new trilogy that begins with its release in 2012." — Official summary
Rocks absolutely can roll down hills in different directions haha but now I don't believe theyre rocks. It's just obvious theyre not Flood, they'd be more distinct to the point where we would be able to definitely define them as flood. It looks pretty obvious that they are inanimate.
I agree that Halo shouldn't have armor abilities and I love the BR way more than the DMR you said it all very well but dude there are playlists with no bloom now.
Because he didn't know Sergeant Johnson came back on a Pelican, the crew of the Pelican that rescued him all died and he came back with John, Kelly, Linda, and Fred
Now since there's the presence of Pelicans I'm thinking that they might split the story of Halo 4 and we might not be spending all our time as Chief. Frank O'Connor did mention in the Halo A-Z that BB was going to become an important AI and he's back with Kilo-Five so my thoughts might be drifting far away here but I'm thinking they might cut between Chief and maybe make cutscenes for what's going on there. Not necessarily have a playable character.
Now also finding out that the part where the groaning sound is heard is where the picture of the Primordium cover is leads me to believe that we just might be dealing with the Timeless One possibly.