It would be hard to over-emphasise how critical voting is for the health of an SE site. Voting is how good content gets recognized, wrong or incoherent content is signalled, and how a class of editors, closers, stewards, and moderators emerge.
This is common advice on new SE sites. Jeff Atwood wrote about it, and it is frequently talked about on metas. But it is also good advice.
Every Stack Exchange site will eventually end up with a different "base level" of voting --- that is, the expected number of upvotes for a question of a given level of excellence. (This effect occurs because people see a good question, but already with a certain number of votes, and think "oh, I would have upvoted this, but it already has enough".)
It's easy for us to affect this "base level" by encouraging high levels of upvoting now. We're setting the standards, and this really will have an effect. A higher base level gives more and better positive feedback to good contributors, and it feels better.
During the Beta phase, voting carries additional weight. Voting shows what constitutes a well-formed question and what is acceptable to the community. If you think that something is useful and appropriate, vote it up. If it's not, vote it down.
We should encourage everyone to vote as often as possible!
