Why is Canon EOS 7d not working?

I did face the same problem with my Canon EOS 7d. It is not dirt nor a normal noise. Do you have sample shots taken at shorter exposure times? Is the noise reduction for long time exposure activated? It looks like"hot" pixels, and perhaps it works against those as well. If it doesn't, then you should give Canon's support hotline a call about it - your sensor may be about to die. Also, a seriously underexposed shot when boosted to a normal exposure during RAW conversion, can look just like that. I think you get it and will be able to click photo without any blurry images.