Remember to clean your sensor as seldom as possible, because:
1. It is a really delicate surface
2. It is hard to get to and your asking for accident. Ona bad move and you can destroy the shutter mechanism, for example.
3. If you clean a lens and you leave a smear or dot that's even 2mm in diameter, you won't see that on you pictures actually, but if you accidentally stain your sensor, small, almost invisible residue will apear as an enormous blob.
4. If you use apertures from open to, say, f11 you won't see the minor dust. Only working on high apertures, such as 16, 22, will empahsize the dust.
5. Be careful with canned air as there is liquid in some of them and it might get sprayed onto the sensor and you're 'done'. I use a typical rubber blower, blow and it works fine. Remember to blow it a few times before actually doing it on the snesor as there might be some dust inside. If you have children, bear in mind that they might have been using it to blow water onto each other, while you were at work, so make sure the blower is clean.
I have shot over 38,000 pictures within 13 months and so far I have a little dust. Luckily my Fuji service wants $25 for cleaning, so I won't fiddle with it myself.