I have done a small amount of research and have found one possible answer to what you are all seeing - I myself see them as well. Not everyone is capable of seeing these specks due to slight differences in the eye structure and even their awareness of it. Just like the blood vessels which cast shadows on the back of your eye, you brain just edits that out of the final image when your consciousness interprets it. These specks may possibly be explained with with the blue light entopic phenomenon. This is the visual phenomenon which occurs when you are able to see the white blood cells passing through the vessels in your eye. Due to their pigment they are not able to absorb light as easily and the red blood cells so they appear in your vision as a small white speck, moving 'aimlessly' through the veins. It is most visible against a bright blue sky, or any solid blue back ground. I even notice them while staring at a computer screen.