Basicly, you place a bet on how much shares the current pool's round will have. Each user can have multiple bets but the oldest one is always used for the current round.
The person that had the closest bet in general gets the full pot.
You can also place a bet that doesn't become active until X hours. PoolBits only has an option for btcguild currently, but other pools will be added very soon.
We know that users since the mtgox breach really want good security, that's why we store the passwords as multiple iterations of sha512+salt.
You can also see on the transaction log each ip that did an withdraw.If you would find any bugs/exploits, contact us and we will be sure to fix these.
1 Bet costs 0.05BTC, there are no fees on bets/wins. There is however a 0.5% fee on each deposit & withdraw.
On the main page you can see all your active bets and all your wins. Every win is made public on the "Wins" page and includes the amount won, the shares the user had and the shares the round had.
On the transaction page you can see every deposit/withdraw to/from your account. A deposit gets marked as confirmed when it has atleast 2 confirmations.
There is no page to see all your bets and/or losses but that will be added in the next few days.
Any questions posted here will be answered, or for urgent things you can contact me at firstname.lastname@example.org
. Or you can join our irc channel #poolbits on irc.freenode.net
(other pools will be added sometime this week and the design is being worked on)