User reports on downrightnow and Twitter today point to a widespread service issue with Facebook:
Facebook has not yet officially acknowledged a problem. If you’re experiencing the issue, be sure to file a report and stay tuned to our Facebook status page for the latest information.
Posted | 4 comments | Facebook, Outages
Many users on downrightnow and Twitter are experiencing difficulty accessing Facebook and slowness loading pages today. The issues may not be affecting all users, but judging by the volume of reports, this is a widespread disruption.

Posted | 9 comments | Facebook, Outages
Numerous downrightnow and Twitter users in the UK are reporting problems accessing Facebook today. Users with Virgin Media Internet service seem to be particularly affected.
We haven’t seen any official acknowledgements from Facebook or Virgin Media, but as always, keep an eye on our Facebook service status page for the latest status information.
As far as we can tell, today’s Facebook issues aren’t affecting a large number of users outside the UK.
Update: Twitter user @ollieparsley found Virgin Media’s official announcement of today’s network trouble.
downrightnow monitors the status of your favorite web services, combining user reports and official announcements to tell you when there's service trouble.