I took a dozen and a half screenshots from the newest Battlefield 4 trailer, "Paracel Storm". Watch it here. I'll leave the news post regarding this trailer to someone else, as I'm unsure of the format and all that.
The trailer itself gives us our first look at jets, scout helicopters, the new BF4 map 'Paracel Storm', and many other things.
The MG4 can be seen in the killfeed, as well as the 'ACE 21 CQB' in the hands of the player.
The Z-11W makes a return in Battlefield 4 (Likely in the hands of the Chinese), as does the Kobra sight. In the clip from which this was taken, the bridge in front of the player also looked destructible.
An ADS view of the AK-12 assault rifle.
The Little Bird also makes a return in Battlefield 4.
A gun as it is being aimed, possibly the SAR 21.
The Gunship's 105mm cannon view in BF4.
An AK-type weapon, probably the AK12.
A view of the scope reticle of the Barrett M82/M107.
A first-person view of a shotgun (that resembles a Saiga to me). A PAK FA (now confirmed) can also be seen doing a fly-by.
A view of the rear of the J-20 from the cockpit of another. A Ka-60 can also be seen.
A new optical attachment, possibly the Chinese holographic sight.
A view from a transport helicopter's gunner seat, likely the Z-9, due to the vane-like projection at the top left not appearing on the UH-1 or Ka-60, and also because the player is on the Chinese team.
A first-person view of the Barrett M82/M107.
The minigun has replaced the Browning M2 on the now-confirmed RHIB Boat.
A cockpit view of the Z-11W.
Another view from the J-20 cockpit. This one better shows the top side of the lead fighter.
An MG4, confirmed by the killfeed a split second after this screenshot was taken.
A view of the TV missile, another weapon available to the new Attack Boats.
THe HUD of presumably the DV-15. Note the 'Iron Fist' countermeasure in the HUD.