How unique does content need to be for google?

GreyWolf said:

Create some quality unique articles or spun articles to submit to the top article directories with backlinks to your main site. Submit those same articles after they've been accepted to the top directories

Click to expand...

Are you saying that I should distribute my article to the top article sites and then after they have indexed it, I should make it a page on my site?

I have an autoblog that only receives posts from a Unique Article Wizard plugin. Now, I am sure that spun versions of these same articles are being posted on 10's of blogs. I have over 21,000 pages indexed in Google. Again, all from not-that-well spun material.

Recently I've been thinking a lot about duplicate content penalty and is it a myth or not... and the more I'm thinking the more I go to a conclusion that it is rather myth. Why?

Well, let's assume we have this scenario... You have a authority website and put everyday really unique content, but 10 or 20 or even more people adjusted their auto blogs to "steal" content (articles, reviews etc.) every time you make a new post. So in just one minute your "unique" content is not so unique anymore, isn't it? Thus it would take your authority site down in SERPs...

Also if dupe content penalty was true, many people would take advantage of this outranking competition by multiple copy/pasting their content to lots of sources, making it non unique.

Its so essential for all....................