Sure it's fun to speculate, but I find it sexist that bloggers are calling January Jones a whore just because she isn't naming the father of her unnamed child because she may not know who that is. Since when do we call a man who has unprotected sex with more than one person a slut?! It takes TWO to tango.. And now it's time for me to be a hypocrite and speculate!

E! reported that January's future baby daddy is Matthew Vaughn, husband of supermodel Claudia Schiffer. The story was pulled within minutes.

Vaughn and Schiffer “abruptly” left town at roughly the same time Jones made her surprise baby announcement in April... [Additionally, Matthew was a no-show at the premiere of his own movie]. His rep [claims] Matthew could not attend the New York screening because of a “severe” case of tonsillitis. Miraculously, though, Mr. Vaughn still seemed quite the chatty Cathy for X-Men interviews on the same day. 

Multiple sources claim that January and Matthew were "very close" throughout shooting. Interesting. Personally, I don't care who da baby daddy is, she just better name the kid February.