This puzzle is part of a series - part 1 is here. Any comments I make on the OP are canonical and out of character (OOC). Any comments I post on answers are for flavour only.
Update: As it turns out, this was a very easy puzzle, and I'm actually having to rewrite the plot of the series thanks to SKV being far too clever for his own bleeding good (I love you really). The glory's gone, but try to solve it without checking out the answers. I enjoyed making it, anyway :-) Part 3 will be tougher.
You're staring at the list of Stacks when out of nowhere, you hear a voice going rik tika tik tik tik tik and before you wonder where it came from you realise something - the capital letters in the titles of all the dead sites can be re-arranged to spell "Moderators"!
You cast your eyes over the the list of murdered sites to find the Moderators Stack, and in your best Scottish-detective voice you announce "Och! There's bin a murrrrrrder, and ah nae where ahm going tae look!" (OOC: Sorry, Scotland). Tentatively, you click through to the Moderators stack and right at the top, you see a post entitled "We Will Conquer". You recognise the title from one of the dead Stacks, so you click on to read it...
You gasp in disbelief and check back to the Stacks list - sure enough, Ask Ubuntu is dead. You're about to click on it to make sure, but then remember the ominous warning about entering a new Stack, and think better of it. This "Handel" character doesn't seem like someone to mess around with.
You realise you're suddenly on a countdown, trying to minimise the number of stacks that die, and every false step you make could bring a flood of confused newbies asking inane questions about anything on to your beloved Puzzling.SE... or even worse, Puzzling.SE might get killed off!
Baffled and starting to panic a little, you sit back to mull things over. What's your next move? Where should you look?