“Sass’s new placeholder syntax is pretty great, isn’t it?”

You say: "I haven't taken a look at it yet, what do you like about it?"

They say whatever.

You say: "Wow, that does sound pretty great, I'll definitely have to check that out." And then you do so, sure.

Human psychology is such that they often will actually react by liking you BETTER than if you had (presumably truthfully) said "Oh, yeah, it's great." Because you demonstrated that you valued their opinion, listened to their opinion, and then told them that they were right on!