By using serif fonts for headings and sans-serif fonts for bodies they have broken the page alignment: the serifs push the headings over by enough pixels to be really noticeable; this kind of design requires really careful attention to optical margin layout (which is, of course, really problematic in CSS).

If this is interesting, you might also like to read the longer post by Wikimedia's Director of UX about the change. https://medium.com/p/1724cb2b7402

I thought I was crazy when I popped in to check something earlier. Bolds look a bit lopsided, especially at small sizes. But it's probably a positive change overall.

The bolded fonts look nasty in Chrome on Windows.

Do you have Liberation Sans or Arimo installed? Or are you on XP with ClearType off?

Typeface hipsters?

These are typeface hipsters:

http://www.fastcodesign.com/3028615/the-beautiful-wikipedia-... https://medium.com/p/1332a0f9eaf0

You may never have thought it in your life, but apparently web users are "design-starved". That must be why Alt-V, Y, N is my very favourite Firefox key combo. Honestly, there's not enough Comic Sans in the world to deal with people like this.