There's no kind way to say it: Windows Phone 7 will be a failure. Announced to much bravado in February as the platform that would breathe life into Microsoft's mobile ambitions, Windows Phone 7 looked based on very early previews as if it might bring something new and exciting to the table. Back then, I noted that I was impressed by what I saw -- with the caveat "so far."

No caveats now: Windows Phone 7 is a waste of time and money. It's a platform that no carrier, device maker, developer, or user should bother with. Microsoft should kill it before it ships and admit that it's out of the mobile game for good. It is supposed to ship around Christmas 2010, but anyone who gets one will prefer a lump of coal. I really mean that.

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The early demos were intriguing due to the use of the card metaphor to organize apps and information, providing a possible fluidity among apps and information that would let users swim through their business and social activities. And the distinct UI -- though based on the unsuccessful Zune media player -- looked as if it would stand out from the crowd of mobile devices that have largely copied the iPhone UI, such as Google's Android, RIM's touch-oriented BlackBerry Storm, and Palm's WebOS.

But that was just the lipstick. Now, in Microsoft's in-depth demo this week at the Mobile Beat conference, there's no mistaking the big pig behind the gloss. Seeing the UI in action across several tasks, not just in a highly controlled presentation, shows how awkward and unsophisticated it is -- I had the same feeling you get when you got a movie based on a great trailer, only to discover that all the good stuff was in the trailer and the rest of the movie was a mess. A pig, in fact.

And it's not just the UI: Under the hood, Windows Phone 7 rests on creakingly old technology that the main competitors have all moved past.

I was appalled, flummoxed, and stupefied by what I saw and the answers to the questions from the 15 or so developers in the audience. Also, it should be noted that minuscule attendance and the utter lack of passion in the room spoke volumes about Windows Phone 7's ultimate fate as well. By comparison, about five times as many people attended a session on WebOS.

The bottom line is this: Windows Phone 7 is a pale imitation of the 2007-era iPhone. It's as if Microsoft decided in summer 2007 to copy the iPhone and has shut its developers in a bunker ever since, so they don't realize that several years have passed, that the iPhone has advanced, and that competitors such as Google Android and Palm WebOS have also pushed the needle forward. Microsoft is stuck in 2007, with a smartphone OS whose feature checklist might match that era's iPhone but whose fit and finish would look like a Pinto next to a Maserati.

An awkward UI that recalls Microsoft's history of clunky design

Let's start with that Zune-based UI, called Metro, as that is the first thing users will see.

Now that I've seen it more in action, all I can say is how clunky it is. You will scroll and scroll to find what you want, thanks to how Microsoft has oversimplified all tasks. Each tile has just a little bit of information -- often just three items -- and you're supposed to scroll sideways via finger gestures to see details on each option in full, then click the one you want to get more details. But if you have more than a few apps in a tile, for example, this approach quickly gets too ungainly, hiding most options and requiring navigation down (and up) several layers of interface. It will be the gesture version of spinning your wheels.

The developers at Mobile Beat quickly recognized the labor-intensity of this UI method and one asked the Microsoft rep if anyone had bothered to test it with users. The answer was essentially "no" -- a scary thought indeed.