Back in March I wrote:
A different metric is how many of the DANE-enabled domains received email from at least 10 Gmail senders in a recent 8 day interval. Back in Dec/2016 I reported that ~2200 out of ~105k domains met that criterion. This month, the number was ~3900 out of ~137k domains. So it seems that a non-negligible fraction of the increase is from real domains that receive email, and not just parked domains.
This "metric" is made available to me informally, so I avoid asking too frequently. The latest update shows:
+---------------+---------------------+------------+ | total_domains | mail_from_5_senders | gt_50_msgs | +---------------+---------------------+------------+ | 173181 | 13393 | 2076 | +---------------+---------------------+------------+
which uses a slightly different "cut-off" of 5 senders rather than 10, so we don't have a direct comparison, but this should be the metric going forward. We we have > 13k domains that get traffic from multiple senders, and > 2k domains with evidence of sustained traffic (over the 8 day sample size).
Just in case this is not clear, Gmail is not presently using DANE outbound, rather I send them a list of DANE domains from time to time, and get back the above numbers.