Change is scary
OK, while the changes are jarring at first, and they do look bloody awful on *wide* monitors, does anyone remember the shit Arstechnica got when they had a redesign? Or the BBC? People hate change.
There are valid points about the amount of white. Allowing a nerd-mode light-on-dark would be nice, but in the meantime a little less glare would be appreciated. Again, check out Ars' Dark on Light theme.
The images are... a bit ameteurish? And having Miley Montana pop up gurning at the top of a page is a bit unsettling at work. Get a graphic artist not an intern.
Columns. Four columns to a page is excessive, particularly as they are fixed in width. Pull out your highlight stories to one on the RHS and leave two columns on the left for your main content. Make them flow with the width of the page as well.
Site looks OK on Mobile IE but too much zoom needed. As others have said, and as you have responded, responsive design is needed but complex. Still, its much better than before.
Keep at it, i am sure you will get to a point where people forget the old site and the new changes bed in.
Or, license the CMS from Ars. And the forums please, theirs is great.