DDOS or crash the game servers. they kept it up for a month with Sony, if they did that shit for the first month of MW3 for online I would.. be forced to go outside and be active. Ewwww...
Honestly if this is for facebook there is a small possibility that they could crash it cause think of it, millions of people are already on it and then depending on how many people who partake in this putting even more strain on the servers, but still very unlikely