I was tracking a few of my own submissions - I think it's random. IF you happen to arrive on the frontpage and stay there for a few minutes, a reasonable amount of people will vote that up. However, if you stay on the front page for too short or not at all, the random fluctuation might kick you down. This is e.g. raspberry pi foundation linking to pypy blog vs submission of the pypy blog itself.
I think it would be great to show one random "new" submission at the bottom of the front page on every page load (it could be marked as "just submitted"). Of course spammers would love that, but I think it would make the discovery process much better, and the end result would be positive.
Not true, it really is fairly random. Usually if it's cool to you it will probably be cool to a bunch of other people. However, the chance that those other people are in a position to upvote it is pure chance. One it gets a bunch of upvotes, then it will stay around in a position that enough similar people will see it and keep voting. Getting those initial upvotes are pretty much pure chance though.
It seems to me that a large portion of cool stuff doesn't make it out from /new any more (not just this case, many others lately)