The biggest frustration for many people is the uncertainty on when they can get into the game. Many people have cleared their schedule thinking they would be able to get in yesterday. Not being able to plan your game seeion is the biggest source of many peoples frustration.
Bioware should try to give some estimated time frames on when they can get in. That would make many people feel content and able to focus on other things rather than checking their e-mails for invite.
The lack of communications need to get sorted thats why the forums are in flames at this moment. Hopefully today bw will handle this much better than yesterday.