Just echoing an important Stack Exchange sentiment from the Vote early, vote often blog post:
Putting voting front and center is very much intentional; it is how good content is voted to the top wrong or incorrect content is voted to the bottom users who consistently provide useful content accrue reputation and are granted more privileges on the site It’s only through voting that a class of editors, closers, and moderators can emerge to help run and govern the site. Voting is how site leadership forms. That’s why the reputation leagues show a breakdown of reputation spectrums.
Voting (up and down) starts the sorting process of questions and answers and shapes the site. It gives people more privileges to properly tend to the site. In a nutshell voting is what makes Stack Exchange sites work.
So go ahead and vote.