raised po ako sa amerika at hindi tinuro sa akin yang mga traditions na iyan ng aking mga magulang. my parents really didn't do that with their own parents and elders either, even though they were very close and very respectful to them. to me, their actions (like taking care of them through the last 15 years of their lives) taught me much more about respect than words and traditions.
when we moved to the philippines i noticed my cousins faithfully honoring these traditions so nakigaya din ako. i didn't really understand it at the time, but "when in Rome...."
my wife's family is big on this, so i make sure i use po and opo with them. also, if i meet a pinoy here in the states who is my elder, i use it too. otherwise, i never do with my own family, and i don't expect my son to use it with me either.