Forum in here looks a bit dead. So is gog version alive? Updates being pushed here?

Yes, it's kept up-to-date. The latest version (0.14.21) is still marked as experimental, but it's there alongside 0.14.19.

I'm guessing most people are talking on the game's own forums instead.

Factorio isn't so much a game to discuss as it is to be played; it isn't very visually exciting (in a sense), but it does hook into the parts of the brain that many games miss, helping ease players into a logical trance.

I found that you can update the game, also update and install mods, from within the game. That's how I got the experimental version to work, however you need to add your seriel to the game's website.