Just curious that if it is going to help serp for the keyword at all? (let's say it's non-related site and no helping with traffic either) did anyone do any experienment to find out if it's going to help serp? I am curious if you build your blog comment backlinks from pages that are all having no pr, would that help? also, what's a good # of backlinks I should get per day from blog commenting?
You'll never know the actual PR of the page you wish to comment on because the toolbar PR is usually out of date and not 100% accurate. When I do my own blog commenting, I usually ignore the PR of the page with the comment section on, not only for the reasons stated above, but because I've already done the hard part (find a good, relevant, do-follow blog to comment on). How frequently you do this is a difficult question to answer. If you vary the anchor text I reckon you can get away with doing it more frequently than if you choose the same anchor text each time.
Why not? I have seen a number of sites who was ranked in google for their keywords because of the number of links they placed on pr0 sites with keyword anchor link text. If you want google to rank you highly on your keyword, one way to do it is get backlinks from pr0 sites with proper anchor text.
I don't think so at all. I think you get no benefit at all from backlinks from pages that have to traffic or popularity. I look for blogposts on high quality blogs, with very relevant content, with good traffic, or at least some PR.
This is true, but if the OP looks at the PR of the page itself, it might come up as PR0, but the blog or site has a homepage PR5. This is why I ignore the PR of the page itself - if the blog has a strong homepage it will likely transfer PR to its inner pages and this won't be visible in the toolbar. Another thing to bear in mind is that a site with PR1 now may be a PR5 in the future. If the blog has the look and feel of a site that is well cared for and the content is good, I skip the PR check altogether. I'm talking specifically about blog commenting here, so I don't have much to lose by adding a comment if I am already on the site. Chances are, I found it by a relevant Google search, so I assume it has some strength if it can rank well for a good keyword.
I wouldn't say that an article is 'likely' to have PR transferred to it. If you look at most blogs, even the most popular one, the VAST majority of articles in them never get any pagerank. I think there's a chance of them getting pagerank. I think if the article has a link to it directly from the homepage then it is likely to get pagerank. Or if the article acquires backlinks of it's own then it is likely to get some pagerank. But the vast majority don't get either of those two, and they end of never getting any pagerank at all.
PR is temporary and not reliable. You never know what will be the future PR of that page. Today it's PR na and the next update it may receive a high PR. Only focus on content. If you think its a good written article which might be useful to visitors then chances are it's going to receive a PageRank for sure, in future. Disable the toolbar and start commenting.
The key to this is that you need a certain percentage of each type of link or google will know you are spamming. This is a good rule. PR0-80% PR1-10% PR2-4% PR3-3% PR4-2% PR5+ 1% This is why you need lots of low PR0 and PR1 links into your site. They may be weak, but if you have hudreds or thousands with good text link you'll benefit.
You'd be amazed, but the authority of the domain has a lot to do with it. Also, the amount of outgoing links on the page. As other people have said, all links help