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Tinkering with the browser status line display is considered poor form. If something is important enough to display, it should be worked into the page itself (<a href="mypage.html" title="about my page"> provides a useful tooltip in many browsers). If it's not that important, why show it at all? You have no assurance that the visitor pays any attention to the status line, anyway.
If people look at the status bar, it is usually to see the status information. This can be especially important if (for example) the link says "Contact Me" and they want to figure out if the link will take them to a webpage with a form on it or attempt to launch their (possibly non-existant) email client.
Some people appear to be under the impression that hiding the URL from the status bar will somehow prevent people from stealing their content or creating deep links. This is rubbish as reading the status bar is probably the last place such people will look, it is easier to copy and past it from the right click menu, address bar, or source code.