helot.org

What can possibly happen if/when Google decides to penalize your site for selling or buying links?This question can be fully answered only by Google, but Google is not a good communicator. You can get some scratch information from here and there and put it all into a logical whole, but the list may never be 100% accurate.

If you buy or sell links this is what can happen to your site:

1. It can lose its ability to pass PageRank. This means that any site that you link to will not benefit from the link. Your site will still retain its PR visible in the Toolbar. I guess you won’t mind this type of penalty. Nothing actually happens. This affects only the sites that you link to and the owners of these sites might be really fuming, but you’re just fine.
2. Your PageRank on the Toolbar or on the search engine may be decreased. This may cause some problems to your site. You may suffer a significant drop in SERPs or become invisible on certain keywords. You definitely don’t want this type of penalty.
3. Drop in SERPs. A lot of sites selling links suffered considerable drop in SERPs. Some SEOs gave a name to this type of penalty “-50” or “-70”. Previous penalty may be combined with this one.
4. Complete de-indexing from Google. This is a capital punishment. Basically the Google guys shoot you between the dot and the com in an execution-like style. If you didn’t like the previous two penalties, you’re definitely not gonna like this one. Even if you type the name of your website in the search box, it’s gonna be out of the Google cyberspace.

Hot to get out of the penalty?

This is from Matt the Knife-Cutts blog:

“Q: What recourse does a site owner have if their site was selling links that pass PageRank, and the site’s PageRank in the Google toolbar was lowered?
A: The site owner can address the violations of the webmaster guidelines and submit a reconsideration request in Google’s Webmaster Central console. Before doing a reconsideration request, please make sure that all sold links either do not pass PageRank or are removed.”
The only thing I would mention is that I would not recommend removing paid links, applying for a reconsideration, and then add paid links back onto the site. That would strike search engines as very deceptive/spammy and could result in sites being permanently removed from Google’s index”

I guess, the only recourse you can take is to remove the paid links (or marked them with a “nofollow attribute”), get down on you knees (translates into admit the violation in the Google reconsideration request), and file a reconsideration request.
What happens then is a great unknown. We’ll have to wait and see how Google responds to these requests.

There is only one little thing left out of this equation. What happens in this whole hassle to relevancy. If your otherwise good site does not show under relevant keywords, because Google suddenly removes it from its index or pushes it down the SERPs, how is that gonna create a positive user experience? Did Google forget about its core priority?