There are certainly some people for whom this will be cost effective, especially if they spend most of their day traveling to places they can be 5-10 minutes +/- their target arrival. However for people like me who live on the east side of Manhattan and commute to FiDi it doesn't actually save a worthwhile amount of money.
Also forbes is incredibly spammy so here's the link directly to the promo: https://www.uber.com/info/plus/newyork/