Google is one of the most successful companies which emerged from the .COMs bubble. Its business model proved itself to be effective and viable.
My own experience with Google main business model started when I developed a website to help people connect with each other without the hassle of downloading software or registering and creating a profile which is time consuming and despicable.
The idea, which I later discovered that was not really new one, was to allow people take a break from what they are doing and have a little chat for five to ten minutes with others chosen randomly by the site. It is just some way of distraction and fun.
Since the server where I hosted the website gave free Google AdWords and Facebook Ads I decided to get use of them. So I put the same advertisement that says "Chat with random people from all over the world" on the two sites and waited.
Few hours later Google AdWords' offered credits were consumed while the ones of Facebook Ads took two days.
At the end, I checked the data and the difference was staggering. The Click Through Rate (CTR) for Google was 0.65% while the one of Facebook was 0.018%. This means Google has beaten Facebook by 36 times.
To explain this difference one should look on how both sites proceed. Google is able to directly detect users' instant needs and respond to it by displaying the appropriate ads, while Facebook uses members profile to guess their needs and show them the ads.
It is logical to think that there is a substantial difference between knowing the need and guessing the need. Furthermore, knowing the users interests via their profiles does not mean they are currently looking for something, while detecting their search keywords will reveal with high accuracy what they are looking for and what they intend to do in coming few minutes or hours.
For that site people were actively searching for ways to easily chat with others without having to do any kind of overhead work and that's what Google provided them while on Facebook people were delivered the ad based on their chatting interest but they never expressed the needs of chatting now or what kind of chatting service they prefer.
For this reason I believe that Google is sitting on a gold mine and will not be easy for any other player in the market, namely Facebook, to dethrone it in the near future.