Music and Age

recently i have thought about what my music professor told me
"you know, when i was a kid, my parents did not like what i listened to, they thought it was disgusting and i didnt like what my parents listen to. It was out of trend and old, but i see my kids listen to hip hop and heavy metal rock and criticize what i listen to, i can understand how my parents felt."

and of course i am a hip hop fan and i started to wonder
will hip hop be old and become something that my kids will criticize me about?

i am a huge hip hop fan and 98% of music collection in my computer and mp3 player is hip hop, other 2% is random songs that i happen to like some classical, some rock, some new rock, some japanese, but never country or emo/punk

so when i grow old and have teenage kids and when they see me listen to hip hop
will they say some thing like "Dad, hip hop is so 2000's, dont you know today's trend is _______, you are so old school."
will they criticize me and tell me i am out of trend?
what will they be listening to?
what will be the trend then?

its an interesting thing to think about
what new genre they will come up with
or what new trend will be
aging is inevitable but trends change every minute