Incidentally, GoG has confirmed they had no idea this was going to happen, so they've been promoting the game on their site for over a month in anticipation of its release. I am sure they are happy to have this bundle!
Oh wow, that sucks for GoG and people who had pre-ordered. I did notice they did a lot of promotion on the site for Botanicula, but they probably also got a lot of pre-orders. So I don't think they should be complaining that much. Unless mass people start asking for refunds, which I wouldn't be surprised if that happened.
Though on their Facebook they (GoG) said that people who pre-ordered are going to get the full soundtrack (not just the 3 track demo) and Machinarium for free. So there's that.
Amanita Design, kind of a dick move.
I hope we all learned a valuable lesson here. Don't pre-order (indie) games and never buy (indie) games at full price, just wait for the Humble Bundle.