My site has been entered in the comment section of many blogs with high PR (PR6).So will make any good ranking for me ? Will search engines go through all links from that site/blog ?
Today a blog use noffolow, it will not help your site to increase your PR.but it will give you traffic.
There are still some sites without nofollow, but they're more and more rare. Comments on digg don't have nofollow.
i think most blogs have nofollow nowadays. i tried posting in a few PR4-6 blogs, around 10, got bout 6 ppl from there (its related to my site niche) in the past 2 weeks. i had say, forget about it, go look for better 1 way backlinks. search free 1 way backlinks and you can get some solutions from a few websites. i don't use such services though, it feels black-hat to me.
Yeah it can be comment spamming but I don't used to spam ! I just get into some blogs and find the real people who are in search of sites like mine and provide my site links to them.
I've notice in google webmaster tools that links from blogs are now indexed as backlinks. It can also be a source of traffic.
Whether or not you recieve a backlink form it they are a great source of traffic. If you offer something usefull on your site it will most likely lead to more backlinks.