Trying to connect to XBOX Live there and it won't sign me in, so I went to 'Test Connection' and everything is fine apart from 'MTU' - what does it mean? membership trial update? because I'm still using the 1month free trial but its not due to expire until March 1st.
I used to have a lot of trouble when I first had my xbox with the MTU, I phoned Microsoft up about it, and they explained what the MTU was, it stands for Maximum Tranmission Unit, which is basically a setting on your router that allows your 360 to work (correct me if im wrong).
But in this case, the xbox servers are being updated/upgraded. I wouldn't worry about it too much. When the servers are back up, and you still receive this problem, then I'd phone Microsoft.