To answer your questions
What will happen after NXT season 2? :They are making NXT season 3 or a Diva NXT
Will the WWE bring it back for NXT season 3?: See answer above
will it be replaced by anew show? : Possibly I think WWE will stick to 3 shows for know.
What will happen to the rookies? : Some of them , Kaval, Riley, and Perfect's son ( I can't think of his name) will definitly go through and be apart of the big brands
Will they all be kept in WWE like the rookies from NXT season before them?: No, and the only reason 4 of those NXT season one rookies are on there is for Nexus purposes, once Nexus disbands most of them will go back to FCW
Will The Possibly join Nexus? No the Nexus' storyline should be over by then
What will happen after NXT season 2? :They are making NXT season 3 or a Diva NXT
Will the WWE bring it back for NXT season 3?: See answer above
will it be replaced by anew show? : Possibly I think WWE will stick to 3 shows for know.
What will happen to the rookies? : Some of them , Kaval, Riley, and Perfect's son ( I can't think of his name) will definitly go through and be apart of the big brands
Will they all be kept in WWE like the rookies from NXT season before them?: No, and the only reason 4 of those NXT season one rookies are on there is for Nexus purposes, once Nexus disbands most of them will go back to FCW
Will The Possibly join Nexus? No the Nexus' storyline should be over by then