Linux adoption rate has suddenly increased thanks to netbooks vendors who went for linux in order to reduce the overall costs. Windows Mobile, which is a popular mobile OS, costs money and thereby increases the overall cost of the device. Linux, on the other hand is free of cost and is open-source, which gives the OEMs much more freedom over what they can do with the OS.
Right now, it is not known when will the first linux based smartphone from ASUS will come out, but we are already so excited about it.