GTA Online Features List

Here's a list of the new info from CVG:

    Characters from GTA V will appear in GTA Online
    GTA Online will not always be limited to Los Santos; additional locations are in the works
    You can do anything in GTA Online that you can do in GTA V. They list the following: heists, co-op missions, gang attacks, death matches, impromptu deathmatch, races, tennis, golf, base jumping, shooting range, ambient events (hold ups of stores, armored van robberies, crate drops, import/export missions involving car theft, bounties that you can set on other players and people can claim), betting
    If you are killed while holding money, you will lose a large portion of it and others can steal it. Use banks to keep money safe
    An in-game smartphone can call your friends whether they are in GTA Online or GTA V. You can also use this to set waypoints for your friends. While using the phone, your avatar moves their lips with yours.
    While you are driving, you can choose to grant someone else permission over the radio
    In-game AI will respond to how aggressive you are on your mic (as in, if you're shouting during a robbery, the AI will react and speed up/become more frightened)
    Whoever sets up a heist decides who gets what cut of the final money when that money is obtained
    Garages range from two car ports to 10 car ports
    Cars can have retractable roofs controlled by the player
    Missions can be accessed by physical markers or through a quickmatch sort of menu
    User-made missions can be favorited and rated
    You can assign other players certain roles in missions based on the particular abilities they have leveled up
    You can share cash and ammunition
    There are stealth kill animations, possibly with a knife. The game tracks the amount of noise your character is making, and the AI will respond accordingly
    You can steal physical items. During the demo, a mission was done in which a bike warehouse was robbed. The bikes had to be transported out in a large truck
    "RP" are the points you get to level up your character
    You can use physical gestures, such as flipping the bird
    All of your info/communications in the game appear in the "Feed." Rockstar mentioned this as a sort of Twitter for GTA Online
    You can purchase insurance for your car. By insuring your vehicle, if it gets destroyed or stolen, you can have it replaced by paying a small premium
    Police helicopters have cameras mounted to the front of them. In real time, you can watch on live TV (on the news channel in your apartment) players with a high wanted level being chased by the police. There are additional channels with programs such as a crime noir show
    Heists can have up to 20 different components. A heist is mentioned where a Titan (largest aircraft) is guarded by "Maryweather" (sp?)
    There is a heli-pad on the roof of (at least) the largest AmmuNation and the store can also be accessed from there
    Off the west coast of Los Santos, there is an another island with lots of buildings. This has not been seen before, but the folks at CVG saw it from afar
    There is a "passive" mode where you cannot shoot or be shot
    Your online world will always be populated with by 16 human players. You can still have friends in the game with you, but the other slots will fill up with random people around the same reputation level, as well

List Source: http://www.reddit.com/r/gaming/comments/1kf2p3/gta_online_announcement_trailer/cbofhxu
Info Source: http://www.computerandvideogames.com/424264/