Kneejerk reaction: Groan.
Way too busy. My head hurts from looking at it (but I'm old so I don't count). I went back to the beginning to read all the current comments and play a bit.
If we will still have the "Classic" option in perpetuity alongside the Beta version, that will be great. I doubt that will happen once Beta goes into production. Will there be a way to limit the number of posts on a screen? I'm getting 40 when I prefer 20. (I should check settings to see if 40 is the default in Beta.) Plus which, when I clicked on "newer," I got a total of 40 posts instead of just the ones I hadn't read. Very annoying.
When clicking "Reply," I wish the screen would go straight to full edit mode instead of having to click again to get there. I guess that doesn't matter in this "spelling and grammar do not count" modern world. Just spit it out and keep going.
Bottom line, I can see the reviews are mixed. Can't please all of the people all of the time. If I can't have the Classic View, I'll just have to adjust to the new Beta one. So it goes.
Good luck to you -- Tom, the rest of the geeks, and the noble Admins who will be fending off the disgruntled hoi polloi.
Edit: P.S. The blue background is much easier on my ancient eyes than the white.