I'm sorry to hear that you're having this issue.
Without this being a diagnosis, I might suggest that if the spots are appearing on the screen (like in a static form), that this is probably a hardward (board) issue rather than the panel itself. I can't say without looking at it, but this does not sound like image retention, but that doesn't mean that it doesn't exist on your panel - but it wouldn't cause this symptom. I would recommend having your unit inspected to determine what the cause is.
I got a Samsung Plasma 50" last fall, and this week it has began showing hundreds of tiny, faint color spots all over the screen. The spots are mostly in waves of yellow and purple, and most visable on a white background. I have seen the spots with both digital cable input and with the BluRay player. They vary considerably, and as mentioned are most noticeable when viewing a scene with a lot of white (outdoors, in the snow, etc).
Is this image retention/burn in? It seems less steady and specific for that to be the issue.
How can I resolve this? Any help much appreciated.