I find the best way to keep that sensor clean is to prevent dust from getting there in the first place, and it can be done.
If some happens to get in, air blow only with Giotto Blower, and do it often, be super fast changing lenses etc, and never, never, leave the camera with the dust cap off.
There just isn't any dust in my optical equipment, I do a quick sensor clean each time the camera is used, I know this may be over kill, but that is me, I hate dust..
leon
