UPDATE 6:34 PM : The Xbox Live support site posted the following status update:
Users may experience difficulties with the following services: Users may experience difficulties connecting to Xbox LIVE. We are aware of the problem and are working to resolve the issue. We apologize for any inconvenience this may cause and thank you for your patience.
Wondering why Xbox Live is not working? It seems that Xbox Live is down due to server problems.
Twitter users are tweeting that they have been experiencing problems with Xbox Live (see the Twitter feed below).
'Xbox Live Down' and other related terms like 'Xbox Live not working' and 'Xbox Live servers down' were among the top searches on Google Trends.
Soft Sailor has some advice on how to check the status of Xbox Live servers:
You can find updates about the Xbox Live servers status on Twitter at the official Xbox Support account here. The Xbox team has acknowledged the server problems and they're working on a fix right now, but they don't know when the outage will be over. Let us know where are you from and if you can play Xbox Live games!
However, it appears that Twitter is also down, so check back here for updates if you're unable to find the Xbox team's tweets.