Yup it can be blackberry (but so far they all have sucky Qualcomm MSM 72XX/6XXX OGL 1.0 chipsets) or Android.
Or the OS that everybody loves to hate: Windows Mobile which currently supports basically everything you throw at it (Qualcomm SnaDragon, TI OMAP 3430, nVidia Tegra etc) and does have a couple of OGL 2.0 devices already on the market (HTC HD2, Acer neoTouch, Toshiba TG01, Samsung Omnia II, OmniaPro..).
Mark Rein said that the announcement will happen at CES, where Microsoft is expected to announce some stuff (Steve Ballmer is the opening Keynote).