iPhone 4 taking blurry pictures pictures taken on my iPhone4 recently became blurry. No software updates were performed, and not water damage exists. Even pictures taken with lots of light show some blur and look foggy.

Anyone else had this problem? - What could be the possible reasons/solutions?
Is there any chance some water vapour found its way into the phone / lens assembly?  Were you using it any place where condensation could have occurred inside the phone?  Radical temperate / humidity changes?  I've never seen this, but I guess it could be possible.  I remember folks experiencing this with first generation iPhones.

Are the foggy bits always in the same place in the photo?