It's not a whole lot of information, but to be honest I think most of it sounds pretty bad.
Firefight was cool. We don't need some potentially lameass story driven mode instead, we already have the campaign. While there are some who like it, how many people want to have their coop game crammed full of story related fluff and a specific plotline anyway?
Man, this was one of the reasons Halo multiplayer was so great. You didn't need to worry about story crap, you just jumped in and shot up a bunch of dudes for wearing a different colour, often resulting in damn good fun. Now it seems they want story to seep through every part of the game, multiplayer too.
Crap, maybe it'd be like spawning in a wall in Forge and then having a big text window come up and detail that particular type of wall's history.
Forerunner vision? Aside from sounding stupid it'll be OP as hell. Sneaking will be rendered useless. I wouldn't be surprised if there's some sort of railgun type thing they'll put in the game that can one hit kill through walls to go along with it, and I'll bet it can see cloaked players too.
Spartan points? Seriously? Are they going to do that thing where they give stuff in their game silly names pertaining to other stuff in the game to try and make it sound cooler and original?
Why Reds and Blues fight, this is completely retarded. So the UNSC has the technology and capability to replicate a combat situation virtually down to the last detail but for decades got their ASSES handed to them by an alien empire primarily armed with laughably ineffective weapons and vehicles, lead by dumbasses and whose military forces are mostly comprised of stupid midgets?
Also why are they fighting each other? Seeing as there's only what, a few hundred million humans left, you'd think the UNSC would consider the real potential future threat to be the Flood/Covenant/Alien whatever. When you think about it, it would make more sense for the SIV's to fight against non-human enemies, which would mean that a VR Firefight type mode which the Spartan's fight aliens in would make perfect sense!
Random weapon spawns? The worst of the lot. I don't think anyone even needs to explain how horrid this will be.
Instant respawn? Bad, considering the absolute suckyness of Halo's spawns.
Join games in progress? This would be great if it weren't for how Halo multiplayer matches are and have always been designed. They'll have to revamp the entire matchmaking system for it to work well.
None of these issues are exactly game breakers for me personally, but if they've already messed up this much stuff how much stuff will they ultimately mess up in the finished game? I think I'll wait for a couple more trailers.