Reply to comment:

Geoff Huston
We performed the same measurement exercise a few times this year in order to see the change when Google's Public DNS service turned on DNSSEC validation - the write up is at http://www.potaroo.net/ispcol/2013-07/dnssec-google.html We plan to measure the state of DNSSEC use monthly, and update the reports as we go. However my good intentions have been swamped by a long list of great projects. I'll try to update this list soon. -- Geoff