I'm not really into statistics and i don't do them regurlarly. But i'd like to remind myself that serversniff.net currently knows more than 19.155.784 unique domains with at least one resolving host. This should be around 15 percent of all known domains on the internet.
we're still adding around 100.000 new domainnames per day, focussing on domains outside of the .com/.net-space. To get a glimpse of domains added take a look at http://tomdns.net - there you can see the newest domains added in realtime.