Thor 2 loses director
It doesn't really matter that Patty Jenkins, the director for Thor 2 is female, what is important is that she has left the production of Thor 2, or more importantly that she left because of creative differences.
Interestingly though the rumour is that she'll end up working on a superhero film for Marvel very soon anyway, just not Thor 2, so the creative differences can't have been that bad.
In fact you would tend to think if they haven't harmed the relationship between the director and the studio then it's probably pretty mutual and they've parted ways because things just haven't been working out.
There's a hint in the rumour, but bear in mind this is Deadline commenting on something that there is no attributable quote for or anyone mentioned in regards the rumour, however they say that Patty Jenkins will work on one of these superhero films but just not a sequel.
I wonder then if she and the studio had trouble with her vision of Thor 2 fitting in with Thor (Filmstalker review) that Kenneth Branagh had brought to life? Perhaps her ideas for the film were just taking it off in another direction? Or there could be the other option that Marvel wants the sequel to look and feel one way with a certain direction and Jenkins just wasn't going to take that route with them. They've been known to push the directors before.
However there's no evidence in the story and it's all supposition, however word is that Marvel are off looking for a new director now and are sticking with the Don Payne script.
I'm sure this is just a blip for Thor 2, and for the relationship between Patty Jenkin and Marvel.