The problem with that is that as you are sucking the dust & air away from the camera...air (with dust) has to rush back in toward the camera...so you may end up with just as much dust.
I think the best would be a simple brushing of the outside and the usual cleaning techniques of the sensor.
That's all that needs to be said. Aside from the issues mentioned it's just not safe. Just google vacuum and sensor cleaning will turn up plenty of horror stories.