Messenger Troubles

Microsoft seems to be struggling with the Messenger service in the past two days. Right now I cannot sign in, I got booted frequently yesterday and yesterday night I could see everybody but chat with noone. What really sucks about that is that I realize how much some parts of work and life have become a dependent on Messenger working - and switching to another service or between services is not really a good answer to the problem. What's the Messenger SLA (Service-Level Agreement), anyways?