Is there another book coming out after Extras? (the uglies series)?

I just read Uglies, Pretties and Specials for the second time.. .and if you havnt read them...omg they are amazing... i finally just read Extra's which i was scared to read at first because i didnt think it was going to be as good...(tally isnt the main character any more) which is why i thought this... but OMG again....im more than half way done reading it and its an awesome book... and tally is in it...YAY... so im really sad to see that this was the last of the series that he has written so far...so my question is..... Is there going to be another book coming out from this series...??? and when???