Yep, that's what they do. They do a good thing, and they do it well. I know a number of people in and around GDS, it's really, really, strange for me to see their name in that list.
To be fair, they are actually very transparent about their use of Google Analytics [1][2], and anonymise some of the data [3]. That is not too bad keeping in mind they share a huge chunk of that data with the public [4][5].
Being transparent doesn't make it right. It (and the fact they use and advocate the use of Gmail in government) worries me. They're the people's government and that implies they're there on behalf of the people, to serve the people. That sentiment doesn't exist at GDS. They believe they're right about everything they do, are recalcitrant and take criticism very badly.