Microsoft's driving home the point that developers are going to know exactly what kind of hardware they're targeting as they whip up Windows Phone 7 Series apps -- and naturally, a biggie is screen resolution since that affects how UI elements are going to be placed, how cool they can look, and how small they can realistically be. In a session at MIX10, Microsoft's Charlie Kindel has laid down the law that WP7S will be 800 x 480 -- just 800 x 480 -- at launch, a message we heard at MWC last month, but the new tidbit here is that there'll be 480 x 320 in the pipe for an unannounced later date. All devices will have precisely the same amount of available RAM and the same capacitive touch capability, and as we've already know, manufacturers will be able to tack on a keyboard if they like.

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