I like how it looks. It's nice to have a fairly-minor shake-up in the aesthetics every now and then, and it makes everything feel a bit fresh and new. And I do sincerely find it fairly minor -- things got a bit rounder and glossier, and there's a few bits of iOS that have some fairly cute glass-distortion effects, and some apps got some not-huge UI redesigns.

Overall, particularly on my phone, it's just giving me an occasional pleasant burst of "ooh, shiny". On my laptop, I admittedly barely notice anything has changed.

(I don't personally have any legibility issues with it, though I'm willing to believe that's down to individual usage patterns.)