I have been in for nearly two hours, no problems... Perhaps they are doing login server maintenance?
I am actually surprised that there haven't been any maintenance sessions this weekend, given all the backed work being done.
It's possible that SE is doing maintenance, but I feel it's just a problem due to people logging on more due to the holiday. I wonder if SE will increase their lobby server when WED rolls around. It doesn't make sense to me to allow more traffic on the server worlds if people can't get though the front door. What concerns me is how Yoshi implied there might be congestion after the new servers come on line if the tests are green. If SE upgrades the lobby server, this won't be a problem. I have a feeling they haven't had time to do this yet. So my personal prediction is that the servers will be a pain to log on due to congestion of the lobby, but if you make it past that, you should be fine. Basically I concur with Yoshi.