"The woman who took the photograph, Adria Richards, soon felt the wrath of the crowd herself. The man responsible for the dongle joke had posted about losing his job on Hacker News, an online forum popular with developers. This led to a backlash from the other end of the political spectrum. So-called men’s rights activists and anonymous trolls bombarded Richards with death threats on Twitter and Facebook." Wow, this…
A taste of her own medicine. It shouldn't have happened, but at least she only got what she gave.
While the original joke was childish, I cannot think of one adult working in any industry who's never said something in a similar vein (or pointing out someone else's phasing might have a double meaning, and so on). It really has nothing to do with gender politics, she was just on a quest and picked up any small examples she could find.
Nobody should have been fired. That's on the employers. However if anyone was going to be fired she deserved it the most, simply because she started this ball rolling on purpose, they were just in the wrong place at the wrong time.