Those sent in the same transaction will have the same lucky#.
This is a trivial consequence of how the lucky# is determined.
I feel like I should chime in here, I have place several thousand bets at btc dice and have yet not to have one come back win or lose, granted the responses have been quite slow lately for whatever reason, and sometimes the transactions seem to get "stuck" but I've had the same thing happen at "other" dice sites as well.
Same here (except not *that* many), but I had become used to rather fast payouts, so a delay of two days *was* ringing the "unusual"-alarm for me.
On a sidenote, I'm wondering about the "value" of 0.00000001 payouts and the byte-cost for the bitcoin network of including these in a new tx. I suggest to BTCDice to offer a second set of bet-addresses, and who bets on those agrees to *not* expect those peanut loss-payouts. For saving them (especially the mining-fee for them), the house edge could be lowered a tiny bit for those bets, as an incentive to save the bitcoin network those peanut-outputs.