Black hat techniques are as dead as the dinosaurs with Google and other search engines giving such practices the strict thumbs down. The emphasis these days is on content. Links are important but are not as easy to build today as it was in the good old days of black and gray hat seo techniques.
A recent development at Google is that the Penguin algorithm will have real time functionalities. In plain terms it means that penalized websites that have taken corrective action will recover from the penalty. Conversely, real time function could also mean that Google will just as quickly block or black list websites that break its norms.