http://i.imgur.com/iISw8fy.jpg
I wonder what this is referencing
Well, to be fair to Shouta and expand on his point: Plus/Minus==Pro/Cons.
Which, again: To be fair, isn't something most reviews do now a days. Yes, they pick apart flaws and explain them but I think Shouta means (haven't ever watched Angry Joe and never will) that AJ provides a quick break-down of "this is good, this is bad, this is good, this is bad" lists that summarizes how they felt about the product.
Magazines used to do this. Some online sites (I think IGN?) do it, but places like Polygon and Kotaku don't because they feel their pro/cons are articulated in the article.