I'm not sure if I addressed that issue or not, but I can see where the 360 network went down. If I recall correctly, I was affected by that outage. But, it was right after Christmas, when people got a new system, and people then had to pick games to play. Naturally, Halo 3 and Call of Duty 4: Modern Warfare were out for a couple months, and that caused them to get on Live as well.
Microsoft was not prepared for that influx, and it showed. Also, I know that I was affected, but my connection was sporadic. There would be times during that week I would have access, and there would be times I didn't. I'm not an expert, but those are signs of an overloaded server.
Still, down is down, outage is outage. I would rather have it due to a spike in gamers than to hackers though.