Dont expect a new D2 version of PvP. First of with the given informations, we wont have any public ratings, so actually its all about join the arena and have fun. You wouldnt know if youre the first of all or the worst. A hidden match making system wont allow you to create personal tournaments. But those are just the informations by now. As we know blizzard, tomorrow everything could be changed.
Im really sceptic about pvp in D3 and hopefully they change theire minds in a more professional way.