The FA's that are posting on Instagram (typically, the younger set) seem to really like the new uniforms.
I must say, they did a great job getting everyone sized into well fitting uniforms, and they've provided a great variety while tying them all together so you know they all work for Delta (contrast that with the old US Airways uniforms where you could have a widebody crew that could have been 8 people off the street, all in different pieces that had nothing in common).
I wasn't sure if I'd like the purple, and I haven't seen them in uniform yet, but the pictures look really good.