@Joshua Parker Ruehlig: You might want to update the first post with a note about manually updating mineOS via "service mineos update" as, at present, manually updating it breaks the web GUI authentication process for mineOS. I don't know enough to comment as to why that is, but the update process spits out a huge amount of errors related to node/posix/npm stuff and then after that you can no longer authenticate.
@Everyone else: I'm leaving a note here as a breadcrumb for anyone else who has run into the same frustrating issue I have. If you run a Minecraft server with the Dynmap plugin (a fantastic little plugin that essentially rubs a web server for you that allows for Google Earth style browsing of your Minecraft world) and you've run into a mysterious issue where mineOS seems to have crapped the bed, Dynmap is to blame. I don't know *why* exactly, but both I (and several people who have posted on the mineOS discourse page) seem to have stumbled on an issue with mineOS and running a server with Dynmap where, at some point after installing the plugin (and seemingly related to the large number of files Dynmap generates) it crashes mineOS. Why that happens is beyond me, but at the moment the solution seems to be simply abandoning Dynmap.