Here's the text of a blog post from AncestryDNA.
We are excited to announce that AncestryDNA has just reached the 2-million-tested milestone. This is a first for any consumer genetic testing company. It was just a little over 11 months ago that we reached the 1 million mark, so the AncestryDNA database has doubled in just short of one year. We now have 2,000,000 people genotyped (DNA tested) who are connecting to family and making discoveries of their own.