Add me to the chorus who saw this and thought it was a horrible change. Thank you for providing for instructions on how to undo it, was driving me crazy (opted out the second I saw the instructions).
My main objection is that I largely could care less about most of the trending topics. They don't appear curated in any way based on my viewing or posting habits so the majority are not relevant to me which means that 75% of the page is taken up by irrelevant posts.
That and it looks horrible.