I have a site for almost 2 years. in january it had a raise in google rankings. this was till the end of April (which means about 2.5k traffic). then it dissappeared for 3 months, for all keywords (which means 0.2k traffic). I had a reinclusion request when the site disappeared. Suddenly , 3 days ago (and after buying articles in some blog nets, during the last week) it appeared in exactly the same rankings for all keywords (which means 2.5k traffic). This was for only two days. Today it dissappeared once again. Any idea? any explanation?
Has you site dropped to the last page of google results ? Has a loss of approximately 950 places ? If yes, your site has the Google's 950 Penalty.
You can find some info about Google 950 penalty here: http://www.articlealley.com/article_176586_62.html
I had the same experience, it had almost dissapeared from google for 2-3 months, now you can think of many explanations, but don't waste your time, if you are not using blackhat seo all you have to do is wait.
the meaning of black hat seo is very unclear nowadays! if buying some links from highly relevant and high quality sites is black hat then yes i have done black hat seo. no it didn't have a loss of 950 places. unfortunately i realise now that it is not in no1 place even for the site's name.. that had happened also when it disappeared for the first time