Accord to my knowledge of American English, people ask
What's you favorite TV show?
and it can refer to anything,even the nightly news.
Is this understanding correct?
Can TV program and/or TV series be used in the above sentence? If so, is there a change in meaning? That is, are the three terms always interchangeable? When might they not be interchangeable?
In your experience, does this usage represent any change over the years, say from the seventies to now?