Since a few weeks I'm very unhappy. My PageRank dropped from 4/10 to 0/10! I really couldn't believe this, but it was true. Today, I checked my pagerank again and I was amazed again. It is 5/10 right now . So it goes from 0/10 -> 4/10 -> 0/10 -> 5/10 I hope I'll reach the 6/10 this year I know some people really don't care about Google PageRank, but I do and also advertisers do! Many advertising companies give you more money for advertising if you have a high Pagerank. In my opinion, Pagerank is still important to me.
Congratulations! Did you submit a reconsideration request after the drop to PR0 or has the PR just returned without you doing anything?
If my site gets PR 8, how many visitors I will get everyday? Can I expect to get something like 6000 or 7000 visitors a day?
Where did you check for your PR? I see no changes anywhere. PR has nothing to do with traffic, it has to do with the quantity and quality of the links pointing to your site. Getting PR8 is not very likely for most sites.