There are so many articles all over the net specially webmaster forums, regarding the issue of duplicate content penalty , but they show you a proof? There are many people maybe including you argue  with me and believe that google will penalized your site if they find out that you are using duplicate content.

The problem in this subject matter is not clear.  When we said duplicate content, is this 100% duplicate of a site, or some part of the site. There are not much prove given by those who are insisting that you need to create unique content for your site else you will get penalized.

If google really penalized site using duplicate content, why they don’t penalize ezinearticles.com , goarticles.com , and other article directories, not only that try to search some blogspot blogs and you will find lot of duplicate content but still they get result from google.

I am not questioning the capabilities and power of google technology and engineers. But don’t you think that comparing all the billions of pages on the net with the page you created need a huge band width and resources. Even do they have the most powerful hardware in the planet but still it takes time. My point here is do they afford to loose this amount of time and ofcourse more cost. Well I will leave to you the question are they really doing word by word basis when they said duplicate content?

On my own opinion if you change title of the page, metas, and add at least 100-150 words before the duplicate content you want to put in your site it will be safe from google duplicate penalty. I have made 5 blogs and sites to test this and this 5 sites and blog never penalized for at least 2 months now.