I realise I made a typo in my comment that meant I was far too generous about the dust alert feature saying it could fine it's arse with both hands, I meant it couldn't find it, not in a million years.
I agree about the loupe too, I bought one which means I often only have to take 1 test pic to detect where the dust is, then use the loupe to check I've got the bits and a test pic to confirm it's gone.
One night I spend 3 hours, I'm not kidding, cleaning the sensor and re-taking test pics only to find the bits had just moved around or that there were even more on the sensor. I took 61 test pics that night, and it gets real tedious taking them, taking the card out, plugging it into the computer, doing the edits to see the dust etc etc etc
Now with the loupe it's fast, having an effective cleaning solution helps massively too, I even have a preset in Aperture especially to apply to sensor dust pics as doing it 61 times that one night was pretty boring too lol