Okay, I retract my previous statement. Even the cleaning lady could've written better source code.
I'm not faulting the code in this case, as in some sort of error having occurred. I have a relatively low number of total votes compared to the frontrunners, so all it takes is a few votes with low star ratings to shift my average downward pretty dramatically. Just four, maybe five votes was enough to knock me from 6th place all the way down to somewhere below 45th and completely off the list.
What I find... odd... is the fact that I had been rising slowly but steadily in both vote count and rating until four or five people all decided to trash me in the span of less than 30 minutes yesterday afternoon. This phenomenon has been noted by others on the Star Trek Online discussion forums and elsewhere. If I were a bit more paranoid, I might suspect something deliberate was going on. The way the voting system is structured, it would be very easy to do.
Whatever the explanation, it's definitely annoying but I'm really not that worried about it. The passage of time and the accumulation of votes should work to even things out, at least to some degree, and I am reasonably confident that the entries will be judged largely on their own merits anyway.