On the StackOverflow podcast they had talked about some of the issues faced with awarding points for asking questions.

Apparently many people feel that asking a good question isn't worthy of points (or as many points) as answering a question.

They at one point (IIRC) were awarding points for asking a question, but that led to people spamming in low quality questions.

My personal rule is that if the question was interesting enough to make me read it, it should probably be upvoted.

They've also recently created a Gold "Electorate" badge, which is defined as "Voted on 600 questions and 25% or more of total votes are on questions." This should encourage people to vote up good questions as well as good answers.

I feel that since there are comments, answering a question should automatically upvote it. It depends on what the criteria for upvoting a question is - whether it's "not spam/trash or poorly worded" then this would work, I feel most people go on "it taught me something amazing/unique" however.

The problem is that it isn't clear WHY you should upvote a question. Upvoting an answer is helpful - I'm saying that I confirm that it's correct and you should believe it - but upvoting a question is just gold star time.

I upvote questions if I've wondered the same thing myself, and it's already been answered. I only use favourite to follow the discussion.