Weather services around the world adjust what is considered "normal" -- in terms of average temperatures and precipitation amounts -- every thirty years. We're now at the end of one such cycle, and so everything that was considered "normal" for the last thirty years is about to change.
This, I think, is such a perfect metaphor, as each generation does the same thing with cultural norms. What was once taboo often evolves into "normal" over the course of time. Some people cling to "tradition," but the truth is that even so-called "traditions" evolve. The only constant, as the cliche goes, is change.
As we enter the new year, one big political change involves the repeal of Don't Ask, Don't Tell. For years it's been considered "normal" for our military not to inquiry into the sexual activities of its members, but if any "deviant" activies came to light, an otherwise stellar member of the military could be discharged with dishonor. That was considered "normal."
Note, then, that "normal" doesn't necessarily equate to "good," whether we're referring to weather averages or cultural practices.
What do you consider "normal"?
"Normal is nothing more than a cycle on a washing machine." -- Whoopi Goldberg