Not really. At least not amongst anyone in my generation. My mom has a harder time talking about it, although it varies with her friends. Another ten years or so and it will probably be as accepted as guys doing it.
I think the reason guys are more uncomfortable with us continuing to masturbate even when we're in a relationship is because y'all are so damn insecure about whether or not you are getting the job done for us you can't seem to fathom that it has nothing to do with that at all, even though it's the same way for you. Again, time will change that, just like time is slowly changing our ability to demand better sex and better sexual partners.