As many of the previous said above, AdWords is helpful for fresh sites, especially if you have a way of monetize the content. But you have to forget about the fact that AdWords will help in Positioning your site better.
Yes will make visible your site, you'll have visits but as ranking the site in SERP that will not happen if you don't do off-site SEO work.
I'm using in most of the new projects the AdWords, especially for low/medium words to see the trend of the visitors and to obtain useful information about the user behavior but nothing more. After 2 months of AdWords you can understand where to focus your SEO campaigns and how to build up your strategy without harming your site with "strange SEO methods".