I'd like to share this on here, because it's hugely crippling to the BF4 Beta experience and it's somewhat hard to dig up unless you know exactly what you're looking for.
If you are in the BF4 beta, launch the browser and load a game but get stuck at the black loading screen (however you can hear the game and people voice chatting) then you should quit out, try and join a game as a spectator, let it load all the way in then quit out and join a game normally. There are a lot of solutions to this problem, but this was the only one that worked for me.
For once, a beta actually feels like a beta and not a demo. I'm not sure if I should be happy about that or not