For those wondering how much of the XPERIA X1 is HTC, Microsoft, and Sony Ericsson, an interview with Todd Warren, Microsoft Windows Mobile VP, at Unwired View, provides some clarification:

The actual experience was done by Sony Ericsson, so a lot of work that we’ve done is to walk this very fine line and create a common platform for application developers and a common course set of experience so a user who picks up a Windows Mobile phone by a different manufacturer can immediately figure out how to use it. Sort of just like any person who gets into a car can find the steering wheel, brakes and the gas pedal; and how to drive that car. But also offering the opportunity for our partners that have expertise in particular areas, to bring those applications to the foreground.

So, the panels, the user interface on Sony XPERIA was done by Sony Ericsson. We provide them some developer support, but it’s all done on open document APIs, any programmer would have access to atop of Windows Mobile.

I have been waiting to hear this. During the Sony Clié days, Sony created Clié Organizer, a ‘Sony version’ of PIM apps with numerous new features, more professional looking, but still maintaining backwards compatibility with the standard Palm OS PIM apps (here’s my original review of Clié Organizer for those who want to read it). Sony has a huge software and R&D team, and I can’t wait for what other new Sony / Sony Ericsson apps they will be including in the XPERIA.

Watch Unwired View’s full intereview of Todd Warren after the jump.