Hopefully it has been driven by the writers wanting to go down a different route, and maybe they have some story lines planned that they simply felt would work better with a female Doctor. Truth is, I doubt that, I think positive discrimination and equality has been the driving force, which...
The reaction post-regeneration has become quite a fun piece. This time, will be interesting. The Time Lord has been a man for 1,000 years, and one with more than a passing flirtation with the ladies, so will they be true to life and get the new Doctor to look straight down her top and deliver...