my last sensor cleaning on my EOS 20D, I needed to perform 8 steps to obtain a perfect result, see why with some explanations and successive sample tests shots after differents steps of the cleaning.

Method used : First sensor brush, second step sensor swab with eclipse cleaning liquid, and then again sensor brush to finish the work.

for the tests shots after cleanings, I shot at F22 out of focus on a cloudy sky, some irregularities that appears on the shots are not dust, but clouds, dusts are clearly visibles as black or grey spots or sometimes little traces.
(I prefer that than shhoting the door of my refrigerator, but it works too...)

Two good sites for e-learning :

http://www.pbase.com/copperhill/ccd_cleaning
or
http://www.cleaningdigitalcameras.com/index.html

BE CAREFUL : SOMETIMES YOU CAN SEE REAL DUST SPOTS, SOMETIMES BIRDS IN THE SKY......