I know it might be a bit late for any major changes to be added to FNV, but then again I loose nothing by posting.

I thought the armor system for F3 was a bit simplistic (a single DR for all damage types) especially compared to the F and F2 armor system (an over all AC, and a DR and DT for 6 damage type).
So I have been thinking of something that would be somewhere in between, and that still makes kind of sense.

First off I think 3 damage types would be enough to cover all the bases.
Impact: projectiles and melee weapons fall in this category. So would shrapnel and fall damage.
Concussion: Like impact but from explosions, things react differently to a shock wave then physical impact.
Heat: flamethrowers goes here, but so would lasers (light energy turned in to heat at the point of impact) as well as plasma (matter super heated to where the nuclears brake apart).

For each damage type there would be 2 numbers. Damage Threshold, and Damage Resistance.
Any damage at or below DT would be ignored. Any damage above DT would be subjected to the DR.
Formula: Damage Done = (Incoming Damage - Damage Threshold) / Damage Resistance

This would make armor choice a bit more interesting. Say leather armor would be great against a flame thrower, but could kind of svck against a assault rifle or grenade. And metal armor would handle grenades and assault rifle well, but be next to useless against a flame thrower or high powered rifle.

have you tried this link? http://www.gamesas.com/bgsforums/index.php?showtopic=1077117

or this link? http://www.gamesas.com/bgsforums/index.php?showtopic=1079722

I think there's a pretty good chances for system similiar to that (DT) to appear. Pete Hines said in the OXM podcast that there'll be a popupicon showing if your current weapon is ineffective against the enemy.

The first link, is more about armor progression and armor looting availability. While my post is more about the game mechanics of armor.
As for the second link, I have already posted the vastly simplifies version a few days ago (that I wanted a armor system more like F and F2), but using that thread to debate a specific suggestion would be a bit off topic. (And annoying to new comers who just wand to se what have bees requested before and write their own wishes)

Personally, I'd prefer a system that had armor absorb a set amount of hitpoints per strike. But if the attack "roll" was high enough, the strike would penetrate through with no absorption at all.

That way you have a choice: If you're skilled enough with a .32 pistol, you can put a round through an enemy's eye socket. Or, if you carry a big enough weapon you could just punch through most armor like paper.

Do not listen to him! Use http://www.gamesas.com/bgsforums/index.php?showtopic=1078988

That does sound good to me, I can say that I'm in favor of making your choice of equipment more of a tactical choice than just "This suit offers more protection than that one so I'll take this one."

This is a good idea, but we already have a few Armor threads. Let's make this easier on the Devs and keep all the Armor posts in the threads that already exist.