Google has been working very hard to make sure that all of their users will be able to get the best results from every search. This is at the heart of the Panda updates they have been rolling out every few weeks. These rollouts have affected a different number of queries each time. Each of the updates has taken into consideration different concerns that Google has had in regards to original and unique links that are organic in nature. They are also worried about content and how it relates to the overall purpose of the site.
Looking at Links
One of the many things that the Panda updates have been concentrating on are the links leading to the website. These eliminated the backlink market that was emerging by destroying the link building campaigns that many sites were using to remain competitive. The switches have continued throughout all of the subsequent rollouts. Each one defines the requirements for a good link even closer. The only thing for a developer to do is to keep up with any alerts for unnatural links and make the necessary changes.
Another thing that the Panda updates have been taking into consideration is the kind of content that is on the site or linked to the site. Every piece of content needs to be unique and has to provide useful content that is related to the overall goal of the website or it will be flagged and your site will not get the results you are looking for. Always make sure that no matter what, you are getting the content that creates buzz for your company and your site through helpful and original content. Any hints of unoriginal or copied content must be eliminated immediately.