GamePro has a few new details
on the Halo 3 weaponry in an interview with Bungie's Frankie, which should help satiate you until the game comes out. You can also view it as a cruel tease (as we do) because we want to try these things out now, not months into the future.
They hint at more grenade options, talk about updating the Assault Rifle, tweaking the Needler, and the Master Chief's ability to dual-wield the Brute Spike Rifle. Which just sounds pretty painful just reading about it.
When it comes to the details we all really need, like when the beta starts, and how big the file will be, they remain pretty tight-lipped. Hand us that upgraded Needler and we'll make 'em talk.