All of Mt. Gox's mail originates from the server w001.mo.us.xta.net. Just check the headers on your account recovery emails. The fact that is shows up in the From address of the password reset email is probably just a mistake on their part.
So confirm that the address is real by looking at the header of the suspect email?
Sure, I suppose it's possible that MtGox just goofed on the reply-to, which of course means that someone requested password recovery for my account and also ploum's (and it wasn't us).