‘CookieMonster’, a user XDA forums has found something very interesting while exploring Manila 2.5.1922 (Sense UI) from leaked Leo ROM 2.02. The code mentions Windows Mobile 7! It does not expose anything but we can get a clue that Windows Mobile 7 may not be too far away from HD2. It has already been announced for HD2 Russia.

if HomeMachineStatus.WM7Device.Value then
IsWindowsMobile7Device = true
PredefineItem = 1
HomeItemCollection = HomeManager:GetHomeCollection(1)
else
IsWindowsMobile7Device = false
PredefineItem = 0
HomeItemCollection = HomeManager:GetHomeCollection()
end

[XDA]

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