I'm all for clarifying the wording.
I'll also take this moment to share a few thoughts on the badge itself. Taken literally:
voted on at least 600 questions
would mean 600 votes for questions, not counting votes on answers.
better than 3:1 answer/question ratio
means more than 3x as many votes on answers as on questions. I'm not sure that's what is intended, but that's what the text says. You might dispute the word "better", but with a literal reading it could only mean a number greater than 3 for the ratio.
That means you need at least 2401 votes to get the badge: 600 on questions and 1801 on answers. Now I know this is wrong based on the update to quack's answer, but it is accurate based on a strict literal interpretation of the text. The actual definition probably just reverses the meaning a "better".
So taking this interpretation, is this a useful badge? As the stated purpose of badges is to encourage specific positive behaviors we need to consider what behaviors this badge encourages. In this case, it seems clear that the badge is intended to increase votes on questions. In that respect, I think might do okay, but I don't know that it will have a lasting impact unless it's effective at creating good voting habits as well.
My main complaint is that this is a one-time gold-level badge. I'll grant it's "bigger" than a silver, but it doesn't quite live up to what I think a gold should be. If you really want to encourage voting on questions long term, I think you're going to need some kind of ongoing incentive. A recurring silver badge for every 250 or so question votes might just about do it.
Also, one additional side effect of this badge is that it will shift some reputation from question answerers to question askers. I think a lot of people consider this to be a bad thing.