I have never seen a GURU becoming a guru from SEO based traffic. If you are purely dependent on the ranking of the sites in search engines - Google or Anything , then beware - you are doomed. ( if not already then about to be)
SEO based traffic model is not sustainable. Ofcourse, in any business you can not predict how the future will be , but especially in SEO, these changes are very rapid and the website owner is completely at the mercy of the search engine - especially Big G.
Google slaps your website everytime they dont like something. Call it with different names , panda,penguin etc.etc. probably their next update would be named as possum. Google has a knack for making the harmless animals look like deadly beasts.
If you own a site in any niche i am sure you have experienced one of these things in the recent past
1) A serious drop in the rankings of your website with out any reason
2) You have excellent content but some crap facebook page ranks ahead of
3) Traffic to your site suddenly dropped.
4) After the google slap, some panda-killer-WSO told you to add insane volumes of QUALITY content to your site - and you did it.
5) Still your website is nowhere in the rankings.
6) You felt like a lunatic marooned on a treeless island.
Welcome to the world of SEO.
Its better to ditch the rankings model and search for something that is consistent.