American Accent Undergoing Great Vowel Shift

http://www.npr.org/templates/story/story.php?storyId=5220090

This webpage has an audio file, produced by NPR - National Public Radio, on February 16, 2006. Robert Siegel interviews William Labov, who talks about how dialects are getting more distinctive nowadays despite the influence of the media. As an example, he mentions a vowel shift happening in inland northern cities (Chicago, Buffalo, etc.). In addition, Labov also gives examples of "mergers", sounds that used to be different and are now pronounced the same. He argues that some local dialects with few speakers are disappearing as they are more likely to merge with the regional dialect instead of adopting the standard English.