The great majority of the gap is due to hours worked and to the types of jobs men tend to do compared to the types of jobs women tend to do. The actual gap (if there still is one) is fairly small and ever shrinking. And with women making up a majority of college degrees consistently for the last decade (or whatever), that will hopefully only accelerate.
I've consistently heard (though I haven't looked at the statistics myself) that the gap was still significant even considering identical jobs with the same amound of hours. Around 20% if I remember correctly. This probably regards France, but I doubt the US are much different for that matters.
The wage gap is a nightmare to get a clear picture off, men and women often work in different sectors which is hard to compare, we also have the fact that woman take long break from their work to get children, which mean they get a lower ancienity and is less likely to get promoted in their job. But yes most experts agree that a wage gap still exist.
