I've made some progress to make free P2P poker a reality in opensource software using the new faster crypo currency engines of Stellar.org and Ripple.com see my github to view the wiki and the present state of my code at https://github.com/sacarlson/pokerth_accounting/wiki that adds a payment modules onto an already existing and popular pokerth software.

pokerth_accounting is ready for testing today not tomaro!! The Mental poker upgrade is mentioned in my wiki as in a future addition that would not be hard to add. The Mental poker c++ libs are already published and tested as seen on another github project that shows times to shuffle well within reason on todays computers. At this point my project is ready for testing. In it's present state we use Stellar.org testnet STR and  trust line generated coins we call CHP (for chips). CHP are a worthless crypto currency that we will us just to keep score at this point and for testing the concept.  The CHP coins  are distributed to member players of pokerth from poker.surething.biz site in a one time 100,000 to start money. As far as other matters that can be a concern like collusion, With the Stellar uncentralized money system were all transaction can be seen by the public. We can track who was playing with who and when on every game ever played to research the possibility of collusion. From this information you can decide weather you want to play on a table with possible colluders or not. I've also added a primitive website that displays all the active members account ballances so you can compare you skills with others at http://poker.surething.biz . This site also contains the database to share your Stellar.org account numbers with other pokerth players. The pokerth_accounting program that runs in the background on your local system does everything invisibly without any added effort from the player of pokerth. After or durring the game you can analize your accounting with an sqlitebrowser to view what you paid who and when. Sqlitebrowser is also used to make changes in the configuration of the system allowing you to change currency or network to real money on a different network like Ripple or other. The software for the most part is completed ready to run but I'm sure we will be finding bugs to fix soon. That's why I need testers. There is no way I can test every function without realtime play involved. So if your willing to help us move this along take a look at our present evolving code at https://github.com/sacarlson/pokerth_accounting/wiki and https://github.com/sacarlson/pokerth_accounting. If you have any question you can find me at #pokerth IRC or even on pokerth game chat as sacarlson or leave me a note on github. Oh and again on the mater of Mental poker algorithm, the present game uses servers that no one ( should say not many) people have access to. So until we start playing with big money I'm not going to wory about it. Remember with Stellar.org that even in real money we can play with very small pots of even less than 1 cent worth of crypto currency of say STR. Transaction costs are so small even in real money (non testnet) the costs would be less than $3 for about 100 years (more than a life time) of play. On testnet in it's present default settings it is completely free. I should note that the next upgrade we are pushing is implementing the built in uncentralized escrow system on Stellar.org. With that and Mental poker added it should be about done. So give it a try and find out for yourself just how close we really are.