@Dan, I, as someone that was not used to write or even read forums, think that when a contest is not awarded and the SH choosing process starts, not only should it be stated here in the forum, but an e-mail should be sent to, to those that doesn't participate here (for whatever reason they might have not to).
I agree with most things that @moretal says, and even when I'm not one to be often benefited, I think the "ranking system" (giving more weight to those with more 5's, then 4's, then 3's) is a good one, but as the CHs suddenly stop rating, the "best entry" mark is a great resource to point out those entries we think are worthy of winning.
I don't know if a SH team gathers around a table with the entries and try to decide which one is the best, or what is their method, but my point of view is that they should gather the entries only, without usernames, and when there is a "tie" on opinions about which should win, then they could see who is the user that sent them and look at their "entries rankings".
Another thing that I wanted to point out is that the "mark as best entry" should not cost points for unawarded contests. They should only take our 50 points when in the ratings process or pending winner, but not on SH choosing. Just my opinion.