Radar has been simplified; no more brighter/dimmer dots for folks above/below you. Now, altitude is obvious: if your enemies are on your level, they're dots. If they're above you, they're small arrows pointing up. If they're below you, they're downward-pointing arrows. It felt almost crude at the beginning of the evening, compared to the subtlety of Reach's altitude display... but that feeling went away quickly, and the utility was highly appreciated by the time we wrapped it up.
I had a little bit of experience with the ordnance drop system. Before talking about what I saw, I'd like to say that I have NO idea how things were set up, and I have NO idea how the overal system works. I only know what I saw. That said: I saw two different ordnance drops. The first was called by someone on the other team; I was running on the lower level of Wraparound, and suddenly saw a green indicator on my HUD, showing me that a Rocket Launcher was available up ahead and to my left. I headed that way immediately. I ran right into a trap. Three members of the other team were standing at the top of the ramp above the RL pod... I was turned to hamburger before I could even pick up the tube. Perfect example of a honey trap... and I fell for it. The second drop was mine - at some point during the game, I was confronted with a representation of my D-Pad, with three weapons attached to three of the four buttons. I hit D-Pad Left, which was linked to a Spartan Laser, and the image disappeared. Soon after, I saw that the Laser had dropped. (It was nowhere near me - clearly, as players learn more about the maps, this sort of thing won't happen as often.) Again - I have no clue what GENERATED the drops; Frank suggested that there are multiple types of drops, and in the games we were playing, these were PERSONAL drops... but I saw that they could be used to supplement your armory (you know about the drop before the other team, and can get to the drop location first), or used to set up traps for the other team (put yourself in position to ambush folks coming to a drop, then give them a reason to walk in). I'll be keeping my eyes open for more details on how these systems work.