Although I'm all for change, I'm finding the new theme a bit much. The color contrast makes things harder to read (at least it causes me eye strain). I also find that the icons on the left hand side that denote active threads, threads that I have replied to etc... are too small to differentiate easily.
When I started making ppt presentations and websites, someone with much more experience gave me some good advice: "The point isn't to look the coolest, the point is to make the presentation easy to read".
I also think that people who are color blind will have a difficult time with the new theme.
Hopefully we will have a choice available to change the theme to something easier on the eyes.
Just my 2 cents....