I like the new Gmail. Others have already written about the new features (snoozing emails, etc), and I admit I don't use those. For those who are worried about the change, here's my quick two cents.

Likes

  • Good-looking dark theme
  • Right sidebar with Calender and Keep is useful
  • Left sidebar can be collapsed. Love this!
  • I previously always used Compact display density. Now I'm using Comfortable because I like seeing the email attachment links/titles, and I keep my Inbox pretty clean.
  • Mark All as Read

Dislikes

  • I wish the left sidebar didn't auto-expand when hovered over
  • Google Keep right sidebar app doesn't allow reordering of list items. Grrr.

Neutral

  • Tasks looks prettier than before, but doesn't really have better features. And it doesn't fit the way I work, because I need to rapidly copy sets of tasks elsewhere. I can do that with Keep. But I think it'll be a good app for many people, especially now that there's a mobile version.

Bonus

The Keep sidebar app puts completed list items in a Completed area at the bottom. Why can't I have this feature in Keep? Several years ago, Google removed some per-list settings, including where checked items appeared. I wrote about this at the time as a step backwards.