Microsoft's Windows Phone 7 hopes to duplicate -- if not succeed -- the iPhone's software achievements. But Microsoft relies heavily on hardware makers like Samsung and HTC to complete the package. Having watched two years of gains in the mobile phone sector slip away, Microsoft is on the brink of elimination. Fortunately, early reviews of the Windows Phone 7 prototype have gushed profusely about the look and feel of the system. Microsoft made our list of top three tech stocks this year precisely because of its one big shot at redemption with a new mobile Windows OS. Microsoft's big edge, if there is any, is in its Office applications. Smarter phones with stronger processors should fit well with Microsoft's effort to run its big, beloved applications like Outlook and Word on phones. The risk to that scenario is that phone makers are getting pulled in many directions, developing phones with Android systems or their own systems. RIM's situation is far less dire than Microsoft's. BlackBerries have continued to win loyal converts in the iPhone era. But RIM needs more than the best email system to keep users happy, namely an improved Web viewer and a host of apps. In an effort to silence critics who say RIM has been dragging its feet on its phone software, the Waterloo, Ontario phone shop previewed a WebKit operating system Tuesday in Barcelona. The company offered few details and said it expected to have phones available later this year.