The thing here is that when properly used, a page can contain several pieces of text tagged as articles, especially blogs with comments (think of article as "an article of clothing", not as "a magazine article"). You'd have to rely on other heuristics to find the "correct" article, which probably is not that much easier than finding the correct div element.
Take a look for example at Fred Wilson's blog http://www.avc.com he is using the article element. You can use multiple times in different blog posts in the same web page and I don't feel this is bad.
