I play a lot here, do you have plan to add sportsbook? If you are bigger and bigger, I hope you should add it.
Well by the name of their site is dice i don't think that they will an sportsbook feature, but surely maybe in the future they will add other games wich is more appealing and playable by their gamblers, so for now lets be settled for the dice itself and enjoy the community what bitdice have for now, and furthermore lets wait for the dev the announce if there will be a big announcement about add ons in this year.
Speaking of sportsbook i dont think bitdice would put this on their website since they have other focus on other games and also bitdice isnt just for dice only you could able to play card game(Black Jack),Roulette and Slot games so this means there are lots of games to choose from that suits your interest.