Well this isn't beta anymore... (so they say...) This is pretty much a limited server stress test. They are testing how much stress is put on the server when numerous people are on. They're goal is about/over 10,000 people, and I am positive they have several servers in which they need to test whether or not people from common parts of the world can join without a problem.
Feel smart, although somebody will find a huge mistake in what I said and I will feel dumb.