Follow the money.
Israeli sources claim that the reason that this information is published at this timing is a German-Israeli drone deal in which the US Predator lost - http://www.defensenews.com/story/defense/international/europ...
They also claim that since 2011 (The last "hacking" incident) there was a major change in the way that drone communication is encrypted.
Edit: changed 2010 to 2011