Not entirely sure if it is set for this season, but if you’ve seen the McLaren MP4-28 video, then it certainly looks like they have altered the airbox area, which could in turn mean that they have added a shark fin.
I thought Mercedes were evaluating this for the FIA? If so then they’d need to be mandated in the rules, which hasn’t happened in the 2013 or 2014 regulations published so far.