Since i am the blog site owner and i know that i am clean with my seo practice, i think google is manipulating the back links quantity making my site below my expectation performance in search engine.

Why google is doing this? We all know that there are companies tied up in Google directly and indirectly. Second the PPC will be useless if many sites is powerful to get the traffics directly. Of course they want the visitors to click on their PPC ads just beside the search engine screen. What can we do? Nothing, since the Google became number 1 they practice and penalize sites according to their own unshared and unfair matrix. They dictate the market and the rules in online marketing.

What a lucky day for us if you experience this. Monitor your back links and see how google managing your inventory.
The following are just my theory and your discreation is advise.