Another bit of info.
I signed up for the latest Xbox live system update preview. My first session with the new OS the was last night and it was much faster.
When in game, bringing up the Xbox live menu using the middle button was instant. I was sent me a party invite and opening this up and accepting it was much quicker. There used to be a delay of a few seconds for the message to be displayed.
Finally, we made it to level 26 on the newest Cod 5 zombie map which took nearly 3 hours. Normally I would be warping around the map after level 20 but there was no sign of this last night.
