Things noticed:
5 man squads
Knife and grenade customization
Variable zoom sights(14x)
Battlepacks
A redone squad spec system
Something which looks like limited ammo for the MBT.
Looks like vehicle gadgets and weapons only need to be unlocked once, or the name for the vehicle could be missing in the alpha.
HUD customization
Two sights on the same weapon?
The map is called Siege and takes place in Shanghai
Possibly an working elevator
Pistol Customization
Barrel Customization
Confirmed Weapons
CZ805
M9 Sidearm
The Scout Elite Sniper
The SV98
The QBU-88 (Which means we can expect to see the QBZ back as well)
The Type 88
QSZ-92
Ultimax-100
CZ3A1
Knife
Confirmed Sights
PKA-S Holographic Sight
The ACOG Sight
The Kobra Red Dot Sight
Confirmed Classes
Assault
Engineer
Support
Recon(Has c4 in BF4)
Confirmed Vehicles
M1 Abrams
PANTSIR-S1
Cougar H
Confirmed Equipment
C4
Confirmed Specializations
The Offensive Specialization