These people called me and said my computer had one hour to live if I didn't compare notes with them on the license number on my computer! Note of warning, check your firewall as I noticed mine seemed to go down for some reason?
I called my brother in law and he said Microsoft (as a general rule) would not call you to let you know, most probably they would send you an email and generally do not have access to your phone number.
I was glad to find this site so I can add my two cents into the what previous writers have already said.
I guess when it happens the first time....you don't throw caution to the wind, the next time your know better!