Perks revealed!

These are some perks that have already been verified in events(E3) to the trailers

Perk 1
Sleight of Hand: Reload weapon faster
Sleight of Hand Pro: Aim down sights faster
Marathon: Unlimited sprint
Marathon Pro: Vault obstacles faster
Scavenger: Loot bodies for full resupply
Bling: Allows two attachments on primary weapon

Perk 2
Stopping Power: Increased damage against enemy players
Stopping Power Pro: Increased damage against enemy Kill Streak vehicles (helicopters, AC-130s, etc.)
Lightweight: Move faster
Hardline: One less kill required per Kill Streak
Hardline Pro: One less death required per Death Streak
Cold Blooded: Makes a player invisible to UAVs, sentry guns, thermal imagery, and air support

Perk 3
Commando: Increased melee distance
Commando Pro: Increased melee speed
Steady Aim: Increased hip-fire accuracy
Scrambler: Jams the radar of nearby enemies leaving only white noise

Death Streak Perks
New Death Streak Perks are the opposite of Kill Streaks: these give the player certain rewards for being killed a certain amount of times in a row without getting a kill. Only one can be equipped to a class.
3 deaths - Painkiller: Triple health for ten seconds after respawn.
4 deaths - Copycat: Copy the loadout(Weapons, Perks, and Attachments) of the enemy that killed you last.

Kill Streak Perks
At the multiplayer reveal event, only the 3 and 4 Kill Streak Perks were unlocked from the beginning. Players can select three Kill Streak Perks at a time. It appears as if a player's kill streak loadout cannot be changed from class to class; instead, one loadout will be used for all classes. Killstreaks now stack (getting a higher killstreak no longer gets rid of the lower unused one, but it will not be available until after the current killstreak is used). There are 15 kill streak perks.
3 - UAV: Deploys a UAV to scan the map and reveal enemy locations.
4 - Care Package: "Air drop a random killstreak or ammo". Deploys by throwing a green smoke grenade. The care package can be picked up by anyone once it hits the ground, including the enemy team.
4 - Counter-UAV: Blocks an enemy UAV.
5 - Sentry Gun: Allows the player to deploy an automated XM312 machinegun. The gun automatically fires at enemies in its line of sight, but it can be destroyed by enemy fire.
5 - Predator Missile: Fires a controllable missile at a designated target area. However, the user is defenseless while controlling the missile.
6 - Precision Airstrike: Initiates an airstrike on a targeted area much like the Airstrike in Call of Duty 4. However, the user can now control the direction the airstrike comes from.
7 - Attack Helicopter: Deploys a helicopter to attack enemy players.
9 - Pave Low: Deploys a Sikorsky MH-53. Described as a more heavily armored attack helicopter which possesses two turrets.
11 - AC-130: Deploys an AC-130 gunship that the player controls. However, the user can not directly defend themselves while commanding the AC-130.

http://callofduty.wikia.com/wiki/Modern_Warfare_2. Good site for modern warfare 2 related news, be warned though it is a wiki and can be edited by people to put fake or unconfirmed info.

Great post, but i just saw a vid on Youtube and you missed one of the killstreak perks. It's a tactical Nuke at a 25 killstreak. The vid showed this in create-a-class mode, so it would be extremely hard to fake. but a 25 killstreak! i've only had 2 of those i think! Is it worth using up one of your three slots for it? here's the vid by the way:
https://www.youtube.com/watch?v=RpP0D5GuAdQ

Edit: sorry, I didn't see how you said that there were 15 killstreak perks, so you knew you were missing a few. Well, the rest are on this vid anyway, but the guy controlling it burns through em so fast, it's hard to tell what some of them are

25 KILL STREAK? what do you get a NUKA BOMB LOL! the closses i have ever come is about 19 i think? Death Streak is a bad idea, its just going to annoy people with a certian ammount of kills that have to kill someone with x3 health come on give us a break. I tell you somethink though these perks may jusy make this game even better than it would have been. Im soo excited! its going to be soo hard to get kill streaks with the enemy having thermal imagery etc...

Yeah, I hope they can balance it well, like in COD4. Also, i think the deathstreaks only last for 10 seconds or so... so odds are you won't be encountering anyone with X3 health unless you're spawn killing, which is a jerk move. And yeah, i found another vid on youtube where a guy got a 25 killstreak on split-screen (no one else was playing) and he used the nuke. It killed him and the other guy, so i'm assuming it just kills everyone on the map. Also, on the description of the perk, it said "End the match with a bang". So it might just straight up win the match for your team...

while your playing on different maps have you found out if the devastation will be noticed? like having holes in walls, bullet marks etc.. because i hate it when you use a tank in WAW and shot right at a wall and it bounces back off. I hope the NUKE idea wont back fire and seem pretty stupid. One other thing im worried about is wether it will get too complicated and put people off :/ shouldn't do but you have to put all this into account.

New death streak has been shown, called final stand...it allows you to crawl around the ground with any weapon before dying (like last stand). The twist is that if you stay alive for long enough you recover to full hp.

Martydom has also been confirmed as a death streak..damn.

Wow..not really a final stand though is it, if you can just recover to full health...

Yeah, that sounds kinda annoying, but it only takes one more shot to finish them, so it won't be that bad. Just hope you don't get killed just as you put them into last stand.