At least in my case. I was having the same problems as you all and after a while it seems it's solved for me. So this is what i made and, appearently solved the issue (3 days playing non-stop in all data centers and no disconnections at all):

I had to format my computer anyway so this step was being done FF issue or not. However, I was using Windows 8 and, for a change, I decided to switch it to Windows 7.

I then reinstalled the game.

Last, i realized that to play i was using the 5ghz network (faster for downloads but as i've heard more susceptible to lag because it's not as strong as the 2.4ghz) so I switch to 2.4ghz when I play. All these together solved the problem in my case.

So I guess you could try them to see if the problem is solved by itself.