Lots of videos having been hitting the web after Activision gave a first taste of MW2 multiplayer gameplay to outsiders at an event in Hollywood.
Game Trailers have many on the Modern Warfare 2 page.
However more interesting is picking apart the videos and seeing what weapons are on offer, attachments and perks.
Primary Weapons
Assault – M4A1, FAMAS, TAR-21, SCAR-H
Sub Machine Guns – MP5K, UMP45
Light Machine Guns – L86 LSW, RPD
Sniper Rifles – ?
Riot Shield – Shield
Secondary Weapon
Machine Pistols – PP2000, G18
Shotguns – SPAS 12, AA-12
Handguns – Colt .44 Magnum, USP45
Launchers – AT4, M79 “Thumper”
Equipment
Frag
Semtex
Throwing Knife
Tactical Insertion
Blast Shield
Attachments
Red Dot
Grenade launcher
Silencer
Shotgun
Heartbeat Sensor
Perks
Tier 1 – Sleight of Hand, Bling, Marathon, Scavenger
Tier 2 – Stopping Power, Lightweight, Cold-blooded, Hardline
Tier 3 – Commando, Steady Aim, Scrambler
Death Streaks – Copycat, Painkiller
Kill Streaks
3 Kills – UAV
4 Kills – Care Package
4 Kills – Counter UAV
5 Kills – Sentry Gun
5 Kills – Predator Missile
6 Kills – Precision Air Strike
7 Kills – Strike
7 Kills – Attack Helicopter
8 Kills – Emergency Airdrop
9 Kills – Pave Low
9 Kills – Stealth Bomber
11 Kills – Chopper Gunner
11 Kills – AC-130
15 Kills – EMP
25 Kills – Tactical Nuke