*** Had to edit to add this (after reading a few other posts). Several of you are posting about the disconnects from the server(s) and are unhappy about it... ARE YOU SERIOUS? IT'S A STRESS TEST. They are giving us a chance to try their game FOR FREE BEFORE IT'S RELEASED. We should be greatful to have the chance and you should EXPECT connection issues in a stress test otherwise they're not doing their job... Am I the only one that sees it this way???????
I hope so, but probably not.
What's the purpose of a stress test? To test the servers under "real world" conditions. The idea is to "stress" the servers with lots of people to mimic what will happen post-release, and make sure things work ahead of time.
From that comes two things - first off, yes, they are letting us play the game "for free", in that they aren't charging money, but it's not like they aren't getting anything from the deal. It would be just as easy to say "Blizzard is getting all this testing done on their game, and they aren't even paying the people they have testing for them!" This is a trade situation - they allow us to play the game, we test their servers for them. They aren't doing us favours.
Second, ideally the servers should be fine already. The game is less than a month from release, that's not a lot of time to fix any problems with the servers they find. The best case scenario for a stress test is that everything works fine. That means they planned ahead, and properly implemented everything they'd need to do in order for the game to be played properly. Personally, I'd hope they would be able to fix disconnect problems by release time, but there's certainly no guaruntee they'll be able to. So while it's not an end-of-the-world situation, it doesn't necessarily bode well for the finished product.