Well, I bought mine around the end of 2006 too. I try to vacuum mine at least once a week, when I am cleaning up my room. So far no problem at all except for once when it hanged and I thought all my save files were gone. I sent it to Sony's repair centre and they managed to get back all my save files still intact. Thank goodness.
And it only hanged once when I was playing White Knight Chronicles. Other than these, it is still working like a good ole machine.