Thank you all for your responses! I found the UI thread after I posted this and I'm glad to see that Evernote did take the time to write a blog post about it prior to its release (even if I'm not a fan of the color palette, that addresses my concern about company communications around it).
I strongly agree with what Piacitelli expresses above. I was quite attached to the established visual "personality" of the UI and, up until the latest UI update, I felt that it had continuity over the years. That said, there is a lot that I continue to appreciate about Evernote's core functionality.