Betas used to be considered dangerous. Now some applications (e.g. GMail) never give up there beta status but just continue adding features.
Microsoft's Windows Live Mail Beta is an upgrade to it's Hotmail email product. It's an excellent product that takes advantage of programs like AJAX to offer an Outlook-like experience with a web based product.
The clincher for me is Live Mail's auto spellcheck. Like recent versions of Microsoft Word it flags your spelling errors a they occur. Adios typos.
