The Big Event is now (largely) finished). If you want to do any more editing, please refer to the earlier guidelines on mass-edits. No more than 5-10 a day, max, please.
It looks like we've been able to edit all (or at least almost all) of the broken image links in double-quick time.
If you still want to help out, others are working on the Star Trek and LOTR tags (see below).
What are our goals and what can I do to help?
The goal is to replace all broken HTTPS links in the shortest time possible, to minimise disruption. There's a Data Explorer query here that will help you to locate the broken links (Don't start from the top downwards unless you want to find a lot of duplicated effort!)
Since the links are broken now, I propose we start immediately, with a goal of completing the task within the next 48-72 hours
Several users felt that it would be a good idea to tag on (pun intended) a retagging event aimed at sorting out our LOTR and Star Trek tags. Assuming they've got a consensus on those we should consider those a secondary objective.