Another vote for the Magic Eraser trick here, I cut off a small corner, wet it and then squeezed all the water out, then lightly rubbed it on the lens in a circular motion for about three seconds and after that the lens was cloud free. Quick and mess free, no chance of anything getting under the lens. Removing this coating definitely affects the quality of the photos though, I now get noticeable glare from every light source in all photos, but before I removed it photos were blurry so it's a slight improvement.
The coating isn't getting covered in scratches as mine was in a decent case and it's very unlikely that something managed to lightly scratch the entire lens surface (rather than some scratches and some clear sections) and also not touch the flash right next to it. it appears to be something causing the coating itself to change from clear to opaque, maybe it's lifting away slightly, or reacting to the atmosphere? I've basically stopped using the camera for anything other than utility shots now because the glare is so bad, hopefully they'll sort this for the m9.