At the end of last year Google did something with its page rank algorithm that caused my site to loose most traffic from Google. I thought the problem was due to excessive load times on my site. I used Pingdom to narrow the load times to a javascirpt from a WordPress contact form plugin. The javascript took about 4 seconds to load and was loading on every page, including pages that did not have the contact form.
Once disabled the load times were down to a more reasonable level, although they have crept back up according to Google Webmaster Tools. As far as I can tell it’s images causing the load times. It was a good exercise for me to understand load times but it was a change made completely on Google’s part that caused the loss in traffic. The site not only got the traffic back but it increased a little. Also, when the traffic did come back the site had a significant increase in comment spam, so much that I had to turn off comments for certain posts.
Meanwhile, I took a much need break from the blog and completely ignored everything (except approving comments) and missed that TechCrunch linked to one of my pages. Causing a nice spike in traffic.