Why would they post something like this on Facebook? This smells like anonymous's work.
Odds are, this is just hundreds/thousands of new people trying the API out after this incident. DDoS by your own prospective customers.
Posted via HootSuite:
https://api.twitter.com/1/statuses/show/314768776577036288.j...
It looks like SendGrid use HootSuite for both Facebook and Twitter - that'd be one way of gaining access to both accounts.