This closely aligns with my thoughts on the issue. While I understand the good intentions behind girl only events, women in CS meetups and girl geek dinners/mentors something about it feels wrong to me. It's like fighting an exclusion problem with just a different type of exclusion and simultaneously reinforcing the divisions they're rallying against.
I think for that reason alone they're a good thing. Could it be taken too far? Sure but I don't see that happening right now, and at the moment given how few women are in our field I think more such things are needed to at least reduce the sharp edges people view from our world.