I'm having a problem that I suspect many marketers share. Quite simply … SEO or just buy the traffic. I noticed that you switched to SEO because you like the passive income component. But when I consider ALL the work and ongoing moving parts to SEO .. visions of the hamster on a treadmill appear in place of couch potato cash. Have you noticed that there is always something new to do … now it's Google+ ect. and "more to do" is surly on it's way. It's reached the point where it's mind numbing.
Or, you could make up a fun game where the first person posts a picture illustrating their pet’s name. The next person has to guess their pet’s name based on the picture. So, if I had a dog named Spot, I might post a picture of a spot. (I did say to keep it simple!) Of course, it’s easy to guess, but it’s also fun and all you have left to do is sit back and watch the comments roll in.
One of the reasons for a traffic drop can also be due to your site losing links. You may be seeing a direct loss of that referral traffic, but there could also be indirect effects. When your site loses inbound links, it tells Google that your site isn't as authoritative anymore, which leads to lower search rankings that in turn lead to traffic drops (because fewer people are finding your site if it's not ranked as highly and more).
In December 2009, Google announced it would be using the web search history of all its users in order to populate search results.[32] On June 8, 2010 a new web indexing system called Google Caffeine was announced. Designed to allow users to find news results, forum posts and other content much sooner after publishing than before, Google caffeine was a change to the way Google updated its index in order to make things show up quicker on Google than before. According to Carrie Grimes, the software engineer who announced Caffeine for Google, "Caffeine provides 50 percent fresher results for web searches than our last index..."[33] Google Instant, real-time-search, was introduced in late 2010 in an attempt to make search results more timely and relevant. Historically site administrators have spent months or even years optimizing a website to increase search rankings. With the growth in popularity of social media sites and blogs the leading engines made changes to their algorithms to allow fresh content to rank quickly within the search results.[34]
Well, yes and no. Sure, you can get hit with an algorithm change or penalty that destroys all your traffic. However, if you have good people who know what they are doing, this is not likely to happen, and if it does, it is easy (in most cases) to get your visits back. Panda and Penguin are another story, but if you get hit by those it is typically not accidental.