Thankfully, GOG were a little late on getting the upgrade so the update on GOG served as a nice reminder. I gave it some brief thoughts back in April of last year and I can safely say it has still left a lasting impression on me.
Here's a little trailer of what to expect:
The updated release adds in "improved visuals, a digital art book and soundtrack integrated in the game, selectable pyjamas, enhanced puzzles and gameplay". On top of that, it also has a new level that gives you a look behind the scenes and a look at some content that was cut from the final game. That sounds like a pretty fun idea!
Thankfully, it is free for existing owners of the game, so there's no need to open your wallets here. I love when developers do this, so existing owners get a better game as a thank you and new purchasers should get a better experience overall.