Very disappointed.
Can't enable shadows for some reason. My guess is the vid card on my laptop doesn't support per pixel, but I have been using shadows with the current 2.20 version for a long time. Sure, I see a bit of a drop when dragging windows etc. but it works fine and I won't be giving up my shadows.
Also, the visual previews from the taskbar are awesome, but completely pointless if you have your taskbar at the top of the screen, as the preview window doesn't drop below the taskbar.
There are other things that are nice, but as those were the two things I was planning on using, well, I will stick to the older version until those issues are addressed.