I'm not sure nofollow links help in getting higher PR or not but the traffic is surely
May be you get high number of backlinks in very short time, please to check you campaign again and readjust
For my own site, I use Google webmaster tool. For other sites I often use by search manually or use Alexa.
Almost high PR and rank sites are nofollow links. I'm not sure that nofollow have no impact on PR and rank. So in my opinion we should have both...
I don't agree with you. Links from high PR site may be prefered in SEO but it is not sured that you link from PR 6 that lead to PR5 for your site
Links may be considered as spam links when you gain too backlinks in short time, and links post in place that is not relevant with the content
I try but it seem not to show all back link.
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