I took a look at your link and can only suggest the points look a bit like hot pixels (assuming not all hot pixels would go red). I'm only speculating but maybe a combination of higher ISO and long exposure has caused them to get a bit hot.
Were you taking a number of long exposure shots in quick succession? This could produce hot pixels. Perhaps our resident guru Neuro might know.
You are right. I took about 45 pictures within 15 minutes, mostly way up to ISOs as high as insane 51k and 102k. Absolutely unusable, though. Well, Neuro, may have another take on that too
@wockawocka: thanks for your input as well! I will take less pictures. I followed examples seen on flickr concerning nightphotography. But yes, I will take it slower next time. As I aimed at "testing" the ISOs for the first time outside, there was a good thread in nightphotography on here, 1Dx vs 5d3 in ISO...Your input will be considered next time I am outside. The only thing is, that it started to look like this right after the first picture I took...as seen in post. Therefore I cannot be a 100% sure if that is a heat issue only...or at least not while I was starting to take pictures...otherwise I just know too less about any camera tech to judge on this...Thanks anyway, your input as all the others is much appreciated! Cheers.