????If this reboot of the Microsoft phone platform underwhelms, CEO Steve Ballmer might have to open the purse strings and make an acquisition. (Hello, BlackBerry!)

????One thing the new Microsoft Windows Phone 7 has going for it is that no one's expecting much. The company's last mobile operating system was clunky, antiquated, and subsequently retired. The Kin One and Two, those smartphone-like pair of devices that Microsoft launched for youngsters earlier this year have already become relics. Even CEO Steve Ballmer acknowledged the company had fallen behind as he took the stage in a Chelsea loft Monday to somewhat tepid applause.

????With phrases like "always delightful" and "wonderfully mine," Ballmer introduced an elegant operating system that, according to the marketing lingo, works with your life instead of taking over your life. "In a sense you could say the differences in the Windows phones are as much about not just what you are going to do with the phone but how you're going to do it," he said.

????Microsoft (MSFT) intends to release nine phones made by LG, Samsung, HTC and Dell (DELL). With support from more than 60 carriers, the phones will debut in Europe on October 21 and come to the United States on November 8. President and CEO of AT&T Mobility (T) Ralph de la Vega was on hand to promote to promote the new handsets, three of which will debut on AT&T for $199.99 each.

????No one's doubting Microsoft Windows Phone 7 is good. The interface design is elegant and intuitive. From first glance, it looks like the designers got a lot of the little things right. In sharp contrast to the confusing kin, the new operating system is easy to navigate. The homepage features six hubs including a gaming hub that connects with Xbox Live. One button allows you to speak your query into the phone to turn up search results. The Microsoft Office hub suggests the phone could be useful to workers on the go. And the company boasts that hundreds of thousands of developers have downloaded the free tools to create apps so far."

????But good is not enough. I'm not talking about a couple of missing feature like copy and paste, which the company promises will arrive shortly. Can Microsoft create a platform that stands out enough to compete with Android and Apple? Will it be different enough that consumers are hungry for it? Will it be pervasive enough that developers want to invest limited resources in making appls for it?

????If there is a company that has the heft to launch a competitive offering, it's Microsoft. Ballmer has spent a reported $400 million to advertise its new operating system, and he has the necessary partnerships with carriers to be taken seriously. But if that's not enough, the company won't get another "do-over." It might be time for Ballmer to set his sights on an external acquisition like the engineering powerhouse Research in Motion (RIMM).