Here's a backlogg if the things noticed on the Neumayer webcam in earlier videos.
This will probably be updated if/when I remember other older things.
The mysterious planet :
The mysterious planet was something supposedly following the sun. As can be shown through YourSky the "sun" in this image (2011-07-14 17:00) is is actually the moon.
The "planet" was clearly seen to the left in the image at 18:00 :
But as you can see in the following images it could be seen transparent in front of the station during an hour before ending up in the 18:00 spot :
So it's nothing more than a reflection of the moon in the camera lens.
The radiation suits.
This image has caused some speculation :
YouTuber foghaze thinks in this video that it is indeed radiation suites to protect them from the earlier coronal mass ejection of the sun. As he found out, there were auroras (and thus much ionic radiation) over Antarctica at that exact date.
I'm not entirely sure though. This is an image from http://www.maydealing.com/2312/products/96075,heat-insulation-suit showing a firefighter's suite, something very similar to what they're wearing :
So my main theory right now is that those three guys were actually doing a fire drill.
Fires happen, even in Antarctica, and you need to have guys on the station able to put it out. It's not as if you just can pick up the phone and dial 911.
As for their pointing, I think it's something they just made for the camera; what are the odds that all three of them just happened to stand and point at exactly the second the webcam took the shot. It only does that once every ten minutes...
Also when was the last time you saw three guys pointing at the same time? One or two, maybe, but not three or more.
The mysterious round shadow
As noticed on the Facts blog the camera is sitting in front of a radar dome. And that's what's causing the shadow:
The reason it's not visible sometimes and changes in size and appearence is that it's illuminated by the moon, and as that goes through its phases the crescent moon isn't bright enough to cast any shadows. You can easily verify that it's the moon by going to YourSky and change the Azimuth to North-West (180° from the South-East the webcam is looking).