Long URLs are not a design flaw -- or, at least, not a design flaw in the site itself. Pagerank calculations by Google and the other engines put a lot of weight on words that appear inside the URL, which is why all SEO advice says to put your blog post titles in the URL (Wordpress has this as an opt-in one-click setting). Long URLs are required by Google. If it stopped requiring them, we wouldn't need long URLs anymore, but personally I find them quite useful most of the time, since it's like a very easy preview of what you're about to click on.