Sgt_Kickaxe - 9:23 am on Apr 24, 2013 (gmt 0)
#1 - Hacked is the wrong word here, trust is probably the right word in as the wrong person was trusted with the password or their computer was compromised and the password was obtained that way. Nobody directly hacked Twitter.
#2 - This was probably a test. What will happen if someone uses an approved Twitter account to spread propaganda? One way to know for certain is to run a test. This was one(intentional or not) that can be learned from.