There must be something within a site that Google really doesnt like. I would check and double check all your content carefully, then try and Google to do another manual review.
My gut feeling is either you still have some nasties left over from your last hack, or someone complained when it was hacked, followed by someone at Google deciding to block your sites.
(how do we get Google to review it? did it get removed from webmaster tools? as I can no longer remember/find it)