Yes but that's only because Yahoo and MS have a deal with Facebook and you don't know how long it will last.

Facebook was explicit in their reply to Google that they feel they can block people exporting their friend's emails. Friend emails are exported by the "export tool" - in fact, you get but a list of names from that.

I would be very interested in looking at the code and noting people's experience with this. One writer was kicked off Facebook for exporting his address two years ago.