Steam Greenlight might be responsible for us getting picked, in a roundabout way:
At GDC our Steam techs told us how we got picked: they were about to institute greenlight, but they had this huge backlog of submissions, and they decided before they moved over to the new system, they owed it to those in the queue to slog through the whole thing, give each one of them a fair evaluation, and then an up/down vote.
So they churned through their backlog in one epic session, and we were at the tail end of it, and apparently they liked us enough to get onto the system. If they weren't moving to greenlight, I'm not sure how much longer it would have taken for them to get to us.
As for Greenlight itself, I've no idea if we would have made it through. We did have a lot of momentum and some great reviews, but I'm not sure I can really play the "beg people for votes" thing as well as others. I'm not good at building a web presence with a high number of daily users, which I think is what it takes to smash through the greenlight wall these days.
I think the main thing that convinced them, given the game's semi-homely visuals, was our direct sales numbers. Of course, that was able to convince them because it reached them in a direct sales pitch. "Hey, you sell games! You should sell ours! It sold this many copies, and we're a bunch of stupid dorks with no marketing budget who have no clue what we're doing! Imagine what it will sell on your awesome platform!"
I don't think fan voters on Steam Greenlight would have cared about a stat like that (in fact it'd look like some weird braggy thing in that context).
So to summarize I have no idea. We totally dodged a bullet.