So, you have been penalized by Google. You think you cleaned up your site and you submitted a reinclusion (reconsideration) request. But you have not heard back from Google. Do you submit another reconsideration request? If so, how soon? That is the topic of discussion at this Google Groups thread.
A webmaster was penalized by Google. He submitted a reconsideration request, but has not heard back. So he continued his/her work to clean up any violations the site may have received. When asked, if he should send another reconsideration request, Google said yes.
JohnMu of Google said:
I would definitely submit another reconsideration request - it might be that there were still issues on your site when it was last processed. I would mention the things you have mentioned here and perhaps even link to this thread.
Based on how John wrote this, I personally would not be shy about submitting a second reconsideration request. If you believe you cleaned up all your issues, then go for it, even if you have not heard back from Google on your first reconsideration request.
But don't submit your reconsideration request when you know you still have issues. It just doesn't look good. It also is a waste for your time and Google's time.
Forum discussion at Google Groups.