So perhaps this is a dumb question (wouldn't be the first time), but I guess I was under the impression that the mods we're in the process of electing would be augmenting those that we already have, not replacing them. Is that not the case? I was thinking about running, but not if it means potentially bumping one of the folks we have now, who are doing a great job...
This site, a post from Jeff, answers it as thus:
However, in the spirit of fairness and representative democracy, pro tem moderators must run for election if they wish to continue on as community moderators.
It's replacing. It's a feature of the Stack site to vote in moderators annually. Our little site is still small, so the available slots are small, but this will grow in time. However, by all means run. I think you'll find that the existing mods will welcome that, though I too agree with your assessment.