My friend has a 4 GB slim, yet Reach (or any Halo game for that matter) won’t let us play co-op. Is this going to be the same case for Anniversary? I think I read that 343 was making it so that Reach will fix this, but I’ve heard nothing on Anniversary.
The Title update did Fix this, it was released a while ago for Halo Reach… But No news has been given regarding if Halo Anniversary’s Campaign Co-Op will Require a hard-drive…
I will research and Let you know when i Can. 
Ok, cool. We’ll at least be able to play Firefight.
That’s a good question. I know for Reach you can play FF and Co-op campaign without a HDD. For Anniversary, i think you’ll need a HDD.