grenv: One of the companies that i do work for (when i am not building) is actually used by site owners / builders to review there websites for user compatibility and friendliness.
Guess what one of the gripes that they get pulled on all the time is ? Navigation of a site
Sites that use the back & forward buttons to navigate dont get great reviews i can assure you.
That and not enough or easiness of help facilities.
Brainking would do very well with things like the context menu & game pull down menu, but not inside an actual game. Take many sites a lot more basic then brainking (bugcafe springs to mind as i was just there) when playing moves in a game there are always 2 option available to you - Undo last move & Restart turn, quite simple, clear and useful things to have, especially in multi-move games like Mancala, Logik, Battleboat plus etc....