I think its more than likely routing problems,rather than specifically an ISP fault. I know all this week,anything going through the clara.net,NTL and Telehouse networks has been affected. And my ISP hasn't reported any DNS problems. Xper,if you are having problems getting on TZ,it might be because there are still remnants of the DDos attack last week trying to filter through.My hosts have had to temporarily block some IP ranges until the ISP's can track down the sources,and block things more accurately.