Fantastic endorsement! I was excited enough to check out how much it costs. The only thing stopping me was that I'd have to get a Steam card. But your description was really persuasive. I watched a couple gamers play the beginning of the game and lost interest. Maybe it's one of those games that you have to play yourself to enjoy.
It also takes some time to get going. They have to introduce the characters, the setting, the atmosphere of what's "normal". And it does take some time. It's the only video game that the characters actually feel like real people to me. And yeah I think you have to play it yourself. That being said, if you are with someone who is watching (significant other?), they'd enjoy it too because they can be a part of the decision making processes which are the largest part of the game.