I believe Digg is better because of the better traffic it sends...
Facebook, Pinterest, Twitter, Linkedin, Google Plus, MySpace and maybe Youtube but it really depends on what you are promoting and when...
check http:// followlist dot com/... you will find there a lot of blog categorized on main areas....
Gretish is right but you deserve congratulation because this is you main business and not many people can say that they are on the first page for...
If you do a guess post you will engage that blog followers to visit your site. If you article is really interesting many will follow your link...
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