According to WikiAnswers "Jon Gosselin stated in an interview that they have recently signed on for 5th season of their popular reality show 'Jon and Kate plus 8' with an option for 2 more seasons after that.
So, there is a chance there will be a 6th and 7th season, it all depends on the Gosselins, the ratings, TLC, the sponsors and the fans." See here;
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I love this show and hope that things continue as long as they can for the children and the fans. I wish The family all the best and hope that things work out be it together or apart.