No smoke without fire as they say. The teams all seemed to be suspicious last year, Ferrari were investigated and it seems have been caught doing something that maybe was a bit on the grey side. I don't want to say they were cheating, but maybe they got something past the FIA and have since removed whatever they were doing and the FIA has let it slide.
Personally, I'd rather the FIA announce any findings that could have impacted the championship last year.