UPDATE The switch maintenance is now complete.
UPDATE: Internap has announced a maintenance window starting Saturday May 16 at 2100 CDT to upgrade the software on the affected switches. They believe that the outage was caused by a software problem which is fixed in a more recent release. There should be no downtime as part of this maintenance.
Between 2000 and 2120 UTC today there were some intermittent connectivity issues which affected all of WordPress.org. In some cases this would have resulted in complete unreachability and in other cases it might have meant a 5XX error or higher than normal response time. The underlying cause appears to be a faulty network switch which has since been removed from production and we are working with the hosting provider to identify the exact issue before attempting to return the switch to production.