What Sharon said.

I think a great deal of the problem today is that mass communication is so rapid that a mispronunciation (e.g., "nucular"), misspelled word (e.g., "alright"), misused word (e.g., "enormity" for "magnitude") or faddish word (e.g, "impact" used as a verb to substitute for "touch," "influence," "affect," "bear upon," etc.) becomes nearly standard usage almost overnight!
This is scary because it threatens the ability of one generation to communicate with people one or two generations removed, not to mention our ability to understand writers who lived many generations ago.
Just as we are greatly accelerating the rate of extinction of species today, so we are unravelling the fabric of our language at a rapidly increasing rate.
I think a lot of this stems from the fact that real knowledge of the language (spelling, grammar, etc.) is not considered an important skill today for copywriters, news anchors, newspaper writers, etc.
Moreover, as someone said above, people today do not welcome correction of their speech or writing the way they might welcome someone's telling them that their fly was open [I know that's awkward grammar] or their slip was showing. Few people seem to value this type of self improvement!

Genie