If your site isn't appearing in Google search results, or it's performing more poorly than it once did (and you believe that it does not violate our Webmaster Guidelines), you can ask Google to reconsider your site. Google Search Quality team today in a Webmaster Central blog post talks abou the improvment made to the reconsideration request process.
In addition to confirming that they've received the request, the team started sending a second message to webmasters confirming the processing of their request.
In the blog post team members writes "We've made a lot of progress on making the entire reconsideration request process more transparent. Although, we aren't able to reply to individual requests with specific feedback, but many webmasters will now be able to find out if their site has been affected by a manual action and they'll know the outcome of the reconsideration review."
"Now, if your site is affected by a manual spam action, we may let you know if we were able to revoke that manual action based on your reconsideration request. Or, we could tell you if your site is still in violation of our guidelines. This might be a discouraging thing to hear, but once you know that there is still a problem, it will help you diagnose the issue," noted Search Quality team.
The team said "If your site is not actually affected by any manual action (this is the most common scenario), we may let you know that as well. Perhaps your site isn't being ranked highly by our algorithms, in which case our systems will respond to improvements on the site as changes are made, without your needing to submit a reconsideration request. Or maybe your site has access issues that are preventing Googlebot from crawling and indexing it."
For more help debugging ranking issues, read this article about why a site may not be showing up in Google search results.