So apparently the Wikia devs are trying out 3 globalnav bars this month. We got the first of 3 today. Unfortunately, it's pretty terrible. The blinding white doesn't match well with our dark theme. Plus it takes up so much space. I have a big monitor, but even then it's annoying since it follows me when I scroll down. Quite a pain in the ass. Fortunately, you're able to edit it on your profile for each wiki by going to Special:MyPage/wikia.css. An example of the one I'm using can be found at http://deusex.wikia.com/wiki/User:ResistanZ/wikia.css. It's still pretty underwhelming, but at least the blinding white is gone. Feel free to use the exact same one or tweak it to your desires.
If you find a way to make it better, please share with us.