I think blog can get more value than forum. 1) Due to more content (Words) 2) Due to Relevant topics more than forum
very important where is the blog link in content or coment http://googlewebmastercentral.blogspot.com/2009/11/hard-facts-about-comment-spam.html
correct, or just install google toolbar and enable pagerank button. then click on pagerank button and select "Backward links"
Correct, a link is a link, but if you are a webmaster, it is far easier to get links from forums. I am of the opinion though that blogspot links are heavier in google's eyes.
Blog links and forum links great sources of PR backlinks if they are dofollow and even if they are nofollow they still can provide some decent traffic as a whole.
I think you get more backlinks from the forums in comparison of the blog commenting....In forums you have a different sections in which you can post your comments on one site.... But in blog you have to search for more.....
Dont think in Google point of view,better you just create back links from all those high PR forums and blogs.
Forum posting is less valuable nowadays because Google sees the IP of the link. I suggest that every should know what is link diversity.
I think blogs are better than forums. However a good dofollow blog that allows keywords / anchor text is harder to find and more time consuming than a forum. Just do what you can, when you come across a good blog go for it. If you can't find a good one or you are wasting too much time, then do some forums.
If both of these are relevant to your site, then follow my recommendation: I think forums get more exposure from search engine, because it get updates more frequently than a blog. But a forum contains too many outgoing links than a blog. So you will get very low link juice. I want to say that outgoing link is also a factor.