6000 Sounds about spot on. What pushed me over the edge was offering my game free on Desura for one day and getting a reddit chain going. I had 20,000 visitors on desura that day! Carefully link to the Desura Game and the Greenlight Page in large lettering if you plan on doing this. If I would have let that campaign run for 48 hours I think I could have gotten all the votes I would have needed in two days. Good luck!! Really love your game.
I also heard that once you are successful with Greenlight and publish your game on Steam, future games can be released directly onto Steam without going through Greenlight again... a few other indie devs have confirmed it but others have said it's "not guaranteed" and "its up to valve".
Valve is very non-transparent so we have no way of knowing. But if true, it's a huge incentive to basically give out your first Greenlight game for free or next to nothing (in bundles) just to pass, then focus on making $ with the next games.
Also, thanks for voting yes on Star Nomad.