http://www.spamhaus.org/sbl/query/SBL214350 Bam, the whole /16 is blacklisted. Maybe people will start reconsider using Spamhaus?
I mean, this will keep happening, more and more people will rent PI space and some will end up in ASNs of spammers, or some people which will resell, for example servers or VPNs, or VPSes. What happened with blocking by ASN? Is that so hard now? Or Resilans are late with the "cut" for Spamhaus ?
Get IPs from others... Because renumbering is easy and this wont happen again.