They incorporated a feature from ftDNA: the ability to assign relationships and notes. In my opinion, 23andMe's version is superior to ftDNA. It doesn't require your match to confirm the relationship like at ftDNA and you can add notes all on the same pop-up page.
At the same time, a new match and I made a connection. I saw on her profile that her surnames included Armstrong, Boyd and Sprouse. These names are all in my tree on the same line. We were quickly able to confirm that we were 4th cousins, our family line having split with the children of William W Sprouse and his wife, Nancy Armstrong.
That same evening, I checked for new matches at ftDNA. I usually look first at the matches who have uploaded family tree. Amazingly, I saw my Armstrong family show up again. This time, our line split at the children of Samuel Armstrong and Mary Boyd.
What are the odds of making two connections from two different companies on the same family line in one day? I need to recommend that they both upload their information to Gedmatch.com where they'll be able to connect with another Armstrong match I've made there.