Don’t get me wrong — I have actually come to like Birthday Facebook, both the notifications and the resulting pile-on of greetings, which seem to me the best purpose that the network has come to serve. But Birthday Skype feels a bit more intrusive somehow, something like your kitchen telephone reminding you that it might be nice if you called your Great Aunt Helen every once in a while.
I did send a quick message of the “wow, weird, but HBD!” variety. I did not, however, send the Skype-minutes-gift-card that was on offer. (Sorry, collaborator.)