Same, I've been trying since 2 hours ago to log in. I'm not sure what is going on at SE's end but I'm trying my best to be patient and hopefully it will be resolved soon.
I guess they really weren't expecting a million people to want to play in droves during first week but that's something I am super happy about. It means SE's subscriber base will be much larger and we can hopefully expect higher quality services/content when they finally catch up! I just hope you can catch up soon SE :P