What Google Analytics say about your site? Does it show some kind of increase in traffic?
You can regularly check the official Blog of Google that is http://www.googlewebmastercentral.blogspot.com
You can create a permanent solution page for each possibility that is not present for your site.
I don't think it changes in a large quantity such as 80,000 to 600. I was also checking the number of back links for my site earlier it said...
Sometime it happens. It can take a longer time than usual to index a Blog or an Article but you have another way to get it indexed fast if you...
Don't worry it will automatically remove from it's index. If you're getting punished for that back link it will be soon recover.
It is both Good and Bad. Good because uploading makes easy to share some information and bad because some people misuse it.
I didn't observe a negative impact for my sites. I think it might targeting sites that depends mostly on Blogs and Articles.
That was temporary ranking. It happens sometimes when you launch a new site and start promotion it first get a good jump in search engine results...
Social Bookmarking was never affected by Privacy Policy and neither it should. Its serving amazingly to websites.
It didn't explain properly what Knol is? Can you share something about this.
Search for No Do follow tool in Google and download a plugin for Mozilla firefox that tells about No follow and Do follow back links.
Separate names with a comma.
