No it will not affect your page rank in any way at all.linking some sites increases your pr?
Yes you can benefit from it seo wise.is it true that you will benefit from it when you put the links of the high pr sites to your blogroll and link list?
hmmm possible but not much.. Because it tried before linking to much sites on my blog decrease my page rank.
I wouldn't even worry about it. If you need to link to an authority site the bottom line is it's not going to hurt you. Whether it helps your PR is debatable but who cares about PR. SERPs are what count.
exactly and most probably for bragging purposes.PR=Size of ...
Unless you are selling links or your site PR is pretty worthless. The only other time is when you are trying to get backlinks.
if you link Wikipedia in a blogpost text, will it still decreases your PR?
The best thing to do is look at wiki, it's one of the fastest growing sites traffic wise, I don't believe that is just down to luck, loads of internal links, a few external links most likely nofollow, doubt they got spammers posting on forums stuff like visit my webpage at wiki, so they are doing something right aint they.
Make sure you are getting links from your related niche and avoid linking to unrelated websites.
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