While your analysis of why we're doing the $10 deal is spot on, we only introduced it a couple of months ago so any benefit we might see is still in the future. Previously the cheapest edition of JIRA was (if I recall correctly) $1200.
It's nice to see that doing good things in the world can also be profitable. (Al Gore just got my company on the front page of the NYT today doing the same thing - so I dig it. :-) )