aacf4497__Blogger__Tumblr_and_Posterous__0
[Blogger.com] Supported. [Wordpress.com] Supported. [Tumblr] Most of the themes support Disqus though you can add any 3rd party commenting service. [Posterous] Supported. [0] 
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Choosing a Free Blog Host - Comparing WordPress.com, Blogger, Tumblr and Posterous
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