Gender Profiling

So, I was just browsing LifeHacker, and it mentioned that Google builds an ad profile for you. So I checked out my ad profile, and learned that Google had assumed, based on my geeky browsing preferences, that I was a guy. Talk about gender profiling! You'd think it would realize how often I hit sites like Pinterest, and that would have tipped it off, but I guess not. I corrected it and opted out of ad profiling.

I won't deny that gender profiling makes some amount of sense. I do it myself sometimes. For example, yesterday, when my RC car robotics team met, my teammate Nathan had brought along a wire crimper/stripper, and was regretting not having brought some other tools. I remarked that I simply didn't have that kind of tool collection, and he said, "oh, you pick things up when you need them for projects". My other teammate, Andrew, had a soldering iron, a power screwdriver, and several other tools for us to work with. They were both regretting the lack of a voltmeter, and Nathan remarked that he was thinking of buying one, to which I replied, "So you can add it to your man collection of tools?"

Well, they got pretty defensive about that, so I dropped it, but see, gender profiling comes naturally to people. The question I guess I want to ask is, when is it appropriate, and when is it not? As a female CS person, I'd say both the examples above (geeky browsing sites and tool collections) are not appropriate gender profiling...but then I'm left wondering what is? I know that there are definitions of biblical masculinity, biblical femininity, and roles for different genders to fill - so when should we fit the profile?