Why .co.cc sub-domains are banned/De-Indexed,Google Answered

According to Google,.co.cc domains were cheap and hence spammy.Matt Cutts,the head of webspam team at Google says-

We absolutely do try to be granular, but I wanted to mention that if we see a very large fraction of sites on a specific freehost be spammy or low-quality, we do reserve the right to take action on the freehost as a whole. I think most savvy search/SEO folks would understand this completely, but I figure it's better to over-communicate than under-communicate.

The bulk domain providers are the main distributors of Spam,Malware and fake anti-virus products.In some cases,Google's automated malware scanner has caught over 50,000 malware sites from A SINGLE BULK DOMAIN PROVIDER!So to prevent their users from malware,Google has recently modified their system to identify bulk sub-domain services which are being abused.So in my opinion,Google did it right,but sympathy with those who lost their earning,weather genuine or not!