Language is constantly changing. We likely sounded very British(at least in the cities) 100 years ago. Hell, if you listen to early recordings of Americans you can pick up British influences in their accents.
The Internet may prove to be an interesting influence on future accents. Before TV our accents were very Locally influenced. TV widens that influence quite a bit, but depending where you live most of the influence was National at most, even then Local still had strong influence on the individual. The Internet changes all that though, now the focus is global and even includes accents from those who speak English as a second language. Due to the highly selective nature of the Internet, it could turn out that each Individual in a Local area is being influenced by different accents.
Even the words we use are going to change. Growing up, I learned Canadian slang in school, American slang on TV, but now I hear British and Australian slang constantly on the Internet.
I don't think it's something to get worked up about. Except the letter Z, it's Zed damn it!
