It seems to be doubly effective to post ASAP after the forum is announced; not only are the most people there to vote on items, but it seems that the way it’s set up, the page of random submissions always has a couple of high-value items at the top of the list. As a result, not only do you get voted on more often, if you get a lot of positive votes, you’re more likely to be on the first page that people go to when voting, making it more likely you’ll get a vote before people get overwhelmed.

My top submission (which I posted Sunday night) doesn’t just have more positive votes than something I put out on Monday; it has five times the total votes. My other submissions may be as good or better, but because it’s usually near the head of the line for reading, it gets a lot of votes.