Hello! So, 10 of my sites(the same ip) has disappeared from Google index yesterday. However, Google bot still crawles it, on Google Webmaster Central it says that my sites are in the index, Google CSE(all my sites are in the cse search engine) says that I have over 20k pages indexed and my sites still have their PR. So, what happens? Am I banned(I am a bit worried, as could be linking a little bit too fast)? Do you have any experience with such situation?
If your sites were indexed for several weeks and then suddenly disappeared, you were banned. There is little you can do, chances are your site won't be indexed again. If they were new sites recently indexed, keep checking back
One site is about 1.5 month old, all the rest has about a week or two. However, these sites has quite a lot of content(takes a moment to get indexed). I have quite a lot of backlinks, mostly social bookmarking, including few edus and govs. If my sites are banned, then why Google still crawles them?
Unique content or 100% scraped content? Post your sites here.. I don't think you will get BANNED from link building to fast, you could be penalized but your site would still show up in google.
Content is unique, however it's not a normal site. It's rather a directory/file listing(sorry, I won't tell more).
Are you talking about the site in your signature? If you are, it's pretty obvious why it was banned. My suggest is to find a better directory script and add some text. There are quite a few scripts out there including http://greg-j.com/phpdl/
New sites sometime come into Google and then go out, give it a couple months before you see what the real potential of your site is. I ranked on a real competitive election term during the election but lost it once the biggies (cnn, ny times etc) settled into the top 10. Now I am nowhere. I view my earlier ranking as the anomaly not where I am now.
Out of the 4 sites in your sig, I'm getting a PR on 3 of them. Google uses multiple databases depending on where your search originated, the load on any particular database, and possibly coin flipping. You can do a search on Google on different days and get different serps, even several times within the same day. Sometimes, things happen, and the database being accessed may have different data, or may be operating from a backup that is not up to date with other databases. These are servers after all, and nothing is perfect. Rather than taking advice that sounds it it came off of a bathroom wall, I'd put more faith in what Google says. If they say your sites are still indexed and your sites are not banned, then the results are, most likely, just not showing when you do a search. Sites do fall off of Google, then get picked up again. I don't have an answer for that, and I doubt Google will give you one. I've seen a lot of sites, or pages within the site, that have been de-indexed. It seems like Google has been buggy lately. You may also want to check out your files, just in case, to see if there are any scripts lurking around that you didn't place there. This does not mean that you positively were not banned or de-indexed, but just because some of your sites disappeared from Google results does not mean that you were banned and will never be indexed again either. Ask some of the other webmasters to do searches on Google and see what their results are.
I think there is still chances your site will come back, some had noticed some update on their backlinks and some have changes in their rankings. Try to submit fresh sitemaps and get some strong backlinks.