Hmm, I am having the same trouble as a fellow above,
Additionally, my friends can see me online and attempt to invite me, but when I accept the invite it says I can't join the party and I'm also shown as SR1 when I am actually SR43 . On my Spartan Hub it shows me as being SR1, but on the small header at the top that displays stats it says SR43. O.o
This problem has persisted since around 9:30 am pacific (nov 26th). I have tried my profile on my other xbox, and I cannot connect there either, whereas friends can connect just fine from my machines. I have access to xbox live and have successfully downloaded a few things today and have open NAT, so I do not believe it to be internet related.
Not sure what I can do personally to help the situation, so please give me a hand here?
Thanks!