Although I most definitely agree with using style guides for various publications, enforcing a prescriptive notion of proper usage on the general English-speaking population is a futile endeavour. The English language has had major influences from other languages such as German and French in the past and is currently undergoing a revolutionary evolution due to modern communications. As one of the most human of all activities, learning language is what each of us does every day of our lives. If you hear a word you don't understand just once, the chances of you recalling it later are minimal. But if you start hearing that word very, very often in specific circumstances, it will only be a matter of time before you start using it yourself in just those circumstances. After all, you want to be understood by others and this is the way we do it. And English no longer belongs exclusively to native speakers nor is it always native speakers contributing to the language. This is typically referred to as Globish or World English. Just one example: Ever use the expression "Thanks in advance"? Up to about 20 years ago I had never heard or seen this used by native speakers, only by students of mine in English correspondence courses when attempting to write "Danke im Voraus", which back then was always "Thank you for your attention and I look forward to hearing from you soon." But Germans starting writing "Thanks in advance" on faxes and e-mails sent across the world and it was only a matter of time before it became a perfectly acceptable and widely used expression in English, also used by native speakers. IMHO, language is all about the frequency of occurrence and statistical probabilities in distinct contexts. If you want to be understood, you should always follow a descriptive - not a prescriptive - grammar.

...and Apple Computers, which may have the power to make the change, is listening... and Apple *c*omputers, [...], *are* listening