Rules
It is played on a smaller board(11x11 instead of 19x19) with a few extra rules.
* In the beginning of the game each player places three stones without seeing where the other player played his three stones. These are called his base. If two stones collide doing this, neither gets the field, instead it turns into a minus zone.
* Two players place a stone on an empty intersection alternately with each player having 25 seconds per move.
* Each move gives you one point
* If a chain of stones of one player is completely sourounded by his opponents stoned/the edge of the board they die and are removed.
* If you run out of your time period, you lose two points and get another period.
* Playing on one of the four (3,3) points loses you five points (they are called minus zone). So forcing your opponent to play on one of them is a pretty big advantage
* If you play on one of the (1,6) points, the marked points on the edge of the board (called plus zone), you get +5 points. Plays on the first line are strategically weak, so you only can do that when no big strategic moves are left, or if you incorporated it nicely into your strategy.
* Regions surrounded by your stones are worth one point per intersection in the end of the game
* Once a game you can place a hidden stone, which is basically a normal move, except your opponent can't see where you played it
* You can once a game scan an intersection to see if there if the opponent's hidden stone is there. This does not cost you a move.
* In the beginning the players bet points to determine who begins. The higher bidding player begins, but the other gets the points the other bet as a bonus.
My Opinion
The hidden stones which the spectator can see, but the players can't make the game more complicated for them, than for the spectators. Still a spectator who isn't at least decent at go or batoo won't understand much of what's going on.
For example I've been playing go for almost a year now (7 kyu), and I can't really tell who is ahead. While I understand their more obvious moves, I don't understand who won, and why, unless it's something really obvious like guessing wrong about the position of the opponents hidden stone.
Generally the hidden stones are their main tool for generating excitement by introducing an element of chance where the spectators know more than the players.
I have doubts that it will be very successful, since it is hard for spectators who won't understand much about what the players are thinking unless they are very strong players themselves. In contrast to this in SC spectators can understand a lot about what is going on, while they can't pull it off themselves due to their inferior mechanics.
Does anybody know how well it is received in Korea? While I don't expect much success the Koreans might pleasantly surprise me. It seems to be running for several month now, but I haven't heard much about it. On TL I only found a rather lacking thread by kona among all that batoo osl stuff.
Videos and more infos:
Jon747/Baezzi has uploaded a few on his youtube account:
Thread about Batoo on a go forum