Originally Posted by KlenTelaris

If a site was blacklisted due content,then all what you need to is to change content and problem solved.After all even if you today have a site which is fully compliant with google policies,it doesn't mean how tomorrow will be as well.
What you need to do,first to check is it domani still indexed
with site:domain.com and info:domain.com search queries,and next step would be to see does domain still rank anywhere with using rank checkers.