this is from 10-david... a hard core, SWAT dedicated fan site:

What is it?
The Stetchkov Syndicate will be the first expansion pack for SWAT4 since its release in April 2005. It is already complete and will be available for purchase by the end of the month (February 2006).

Will this FAQ just feature the author having a simplistic conversation with himself?
Good question. This FAQ aims to gather together all the information we know about The Stetchkov Syndicate into one handy resource. Nothing wrong with that, is there?

Not at all! So what's in it?
An Eastern European crime family has taken up residence in SWAT 4's hometown, bringing with them more guns, drugs, and criminal activity. The SWAT team will take on this new syndicate in seven new single player levels. Unlike SWAT4's original missions, there is a storyline linking the new missions together.

NEW LEVELS
Seven in total, for both single player and multiplayer. Described by GameSpot as "bigger, tougher, and more tactically challenging that anything you experienced in the first game." Includes a subway station, a large nightclub and the bomb-ridden Ministry of Agriculture which looks set to become a cult favourite.

Producer Paul Pawlicki provides the plan: “The Stetchkov Syndicate takes place in the same city as before, so we stayed with the urban look but added new locations. Irrational does grim and gritty very well and you will see that same attention to detail in all of the new levels, like the drug lab and the halfway house. Some levels, like the subway, were designed to be much larger in order to take advantage of the new weapons.”

NEW EQUIPMENT

There are roughly a dozen new weapons and tactical items, some are team specific while others have to be “unlocked” by completing missions.
40x46mm Grenade launcher for firing non-lethal projectiles (gas grenades, stingers, flashbangs, baton rounds)
Cobra Stungun - a Taser with added Touch-Stun melee attack (bit like the Electrogun in GTA)
New SWAT weapons include Colt sniper rifle, 5.7x28mm Submachine Gun (P90)
Suspects get new 5.56mm Light Machine Gun, Mark 19 .50 Semi-Auto Pistol and 9mm Machine Pistol
Night Vision goggles - which give you a limited view in the dark (see screenshot on right) but cannot be worn along with a helmet, leaving you exposed to flashbangs etc.
Chemical Lightsticks/chemlights/glowsticks/coloured rod allowing you to mark cleared areas
Your, erm, fist. You can now hit uncompliant baddies.
Option of an Additional ammo pouch, at the cost of another piece of equipment
SINGLE PLAYER IMPROVEMENTS

Compliant, but unsecured, suspects may now become a threat again. Previously they were no longer active, but now they can run away and/or pick up arms.
"Held" Commands. "Held" commands are only acted on once the "Go" command is given, allowing, for example, simultaneous entries.
Suspects may now used blind suppression fire.
Evidence at a crime scene may be destroyed by the suspects if they are alerted to SWAT’s presence.
MULTIPLAYER IMPROVEMENTS

Built-in Voice over IP giving team-mates the opportunity to communicate using a microphone at the press of a button.
Up to 10 players in co-operative mode (allowing two 5-man teams, rather than just one)
"Unique Leader" in co-op, allowing just one player to issue commands
”Vote kicking”. At any time, any player will be able to initiate a vote to kick/ban an annoying player from the game, or even change the map or game mode.
New multiplayer mode: Smash and Grab. The team of suspects tries to grab a randomly-placed suitcase and escape the level with it, while the SWAT team tries to hold them back until time runs out.
-The suspect carrying the briefcase must move at walking speed and can only use his sidearm.
-Every time SWAT arrests a suspect, 30 seconds are taken off the time remaining. (Also optional in other multiplayer modes)
Improved Quick Mission-Maker allowing you to make missions "on the fly" and play them online.
Skin chooser allows you to use user-created skins for your character. [How to?]
"No Armour" option – everyone moves faster but die quicker
New stat tracking/ladders/rankings