My take on Joss Whedon is that he is an advocate for active women in Sci-fi/comics, but I wouldn't say hes any more of one than George Lucas. Whedon's tend to be *strong* women, not necessarily strong characters even. Zoe is the one exception, certainly not Buffy, and lets not talk about what the heck went off the rails with Dollhouse. I think Lucas' treatment of Leia is just as strong, if not more so considering it's almost 2 decades earlier.
I think the assessment of Martin's portrayal of female strength is perhaps more fair, but again they tend to be strong in the face of some form of adverse conditions or other manipulations in the books, it hasn't played that way as much in the TV show. Though Martin is dealing with a different genera being far more Fantasy than Sci-fi. Which I think is an important distinction. Fantasy has always allowed for a more active role for women and has been marketed toward women as much as men. Sci-fi/comics on the other hand tend to be much more male oriented and the female characters reflect that. I think the same thing can be seen with video games as well. Generally there is a marketing perception that these things don't appeal to women, so there is no effort to make them do so.
I think Sherrilyn Kenyon's books (which started out heavy on paranormal romance and have moved towards more general sci-fi/fantasy though they're still shelved with the romance novels except the kids & graphic novel versions) provide good strong female characters, They've recently been optioned for movie/TV and I'm interested to see how the translation goes.
Related to Game of thrones the series, I think the fact that they didn't do creative hiding of the male nudity was also a rather surprising choice, even on HBO. And I think encouraging to see the quasi equal treatment. BBC recently ran an interesting article adjacent to that here http://www.bbc.co.uk/news/magazine-20218094. The fact that full frontal female nudity is not even particularly surprising when it shows up in films or TV shows while full frontal male is is another interesting split how genders are viewed.
I'm kind of headed off on a tangent here, but I didn't want to side track the Avengers thread any further. And with being out of town for the holiday I kind of missed jumping in on that discussion.