Ever since I started using MissionControl (which has been since 1.5 or somewhere around there), the admin template styling always changes whenever I open up one of the front-end templates and click save. All I have to do is go into the admin template and save that again and everything's back, but it is kind of annoying.
Additionally, I've noticed since 2.3 was released (maybe before then and I just didn't notice it) that the title is messed up whenever I open a template put out by Gavick.com. It's the strangest thing.
I'm not sure what the deal is what that gavick template messing with the format of the header, but i'm pretty sure its related to some CSS that the template config is loading up. There are similar problems with the sidebar showing those icons as with the gavick slide show extension. It doesn't seem to be doing anything malicious, just looks bad. I'll sort that out as soon as I have a test extension to replicate the issue with.
Regarding the template losing styling when you save a front-end template, that was an error in the way i was checking the current template. That has been fixed for version 2.4.