If there's a better forum for this (I haven't seen one) please let me know.
I've had an SX120is since before xmas and have been helping out with the CHDK port and I've been noticing more and more particles of dust *under* the lens over time.
The one thread on the net that mentioned such a problem with Canon cameras said this isn't an uncommon problem with cameras that have large lenses that retract and suggested attempting to suck the dust out with a vacuum cleaner. Carefully.
I've had no luck with that and Canon has suggested sending it in to the nearest repair center but won't say if it's going to be covered under warranty.
Anyone else seen this problem? If you aren't sure, in bright sunlight, turn on the camera and extend the lens all the way and see if you can see particles under the lens. It'll be fairly obvious as the dust will be below the top of the lens if there's any under there at all.