Not gonna lie: I had a little smile on the face, when I discovered the "new GOG logo".

Yeah, I noticed it right away. Is it related to Stalker 2 and it's release or is this the new gog logo for the foreseeable future?

Odd. Still the same logo for me.

Yes, it's just a visual gag, related to the game's release.
I highly expect it to vanish again, once the "S.T.A.L.K.E.R. 2 release week" is over. That's just "Good old GOG" at work again...different groups of customers see different versions of the store.

Btw: it's still visible for me.

They used a script hosted externally (Google Tag Manager - apparently it was a quick hack ;)) so it may be blocked by uBlock and the likes.

FEMA upgraded GOG's hazard level from toxic to radioactive!

That's what they always do. ;)

I'm also still seeing the old non-radioactive logo. I'm going to just roll with it and say that GOG knows that nuclear isn't well liked over here in the state that I'm in.

Right you are. It was being blocked by NoScript in my case.