The world is more or less a globally integrated village in this day and age and the internet is responsible for this. Given this situation, using the internet to advertise isn't really a bad option. In fact, all over the world it is being considered as one of the best options- cost effective, super-fast and reaches an audience of millions. Social media marketing via the web is becoming an increasingly viable option in terms of internet marketing.
Look at the number of advertisements on Facebook for example. With over a billion users, it has become one of the most popular social networking websites in the world and that too in a matter of a few years. Interestingly, it is one of the most effective forums for marketing a product of a service primarily because anything on Facebook spreads like wildfire. You see a page, you like it, your friends see you've liked the page in their news feed, they like it, their friends like it, and so it goes on. The complex spiral of viral marketing on Facebook and the fact that the website supports and provides various functioning options for ad pages, etc. makes it one of the best websites supporting social media marketing.
Then again if you keep your eyes open you'll see the tweets from some birdie with thousands of followers; of course we're talking about Twitter, with an extremely wide user base including celebrities. Some prominent companies like Blackberry have taken to being on twitter to understand what the potential consumer base is looking for in a phone. This only goes to highlight the fact that even surveys of market behaviour can be conducted at minimal cost on social networking platforms. If something becomes popular on Twitter, people around the world will know about it and will want to own it. And that is the ultimate goal of advertising- to make people want it. Like they say, a tweet is worth a billion words, and if you don't believe that, put your idea on Facebook and see how it sells.