Edit: I'm not suggesting that Ensure and soylent are identical, but there is a lot of overlap, and in this case it appears to satisfy a lot of the requirements in the parent comment.
It's interesting to me when something like this comes along and people herald it as something completely ground breaking when there's already a myriad of products do this and probably taste infinitely better.
Not saying its a bad idea, but this space is already incredibly crowded. what's the selling point that Soylent has over its competitors?
Ensure doesn't even get you close to the recommended amount of macronutrients, unless you're trying to lose weight. Ensure has 210-350 calories [0], yet high levels of micronutrients which means if you drink too many of them you risk taking in way too much of some vitamins and minerals.
Soylent is meant for healthy people who want to consume a normal amount of macro and micro nutrients each day.