@ Rokudaime Sennin..
No. It's still his Sharingan eye. If you think about it; he has to keep the sharingan. Having a Sharingan and Rinnegan is what makes him " godlike ", if you know what I mean. Also, having those two doujutsu's / having already uchiha bloodline / manipulation DNA of 1st Hokage.. that's what makes Madara the 3th Rikudou.
- Besides; if his teleportation / dimension jutsu is related to the sharingan ( I STILL believe that this was his extra doujutsu that he gained after awakening EMS ), then he won't replace it with another Rinnegan Eye. IF MADARA stills tries to execute Moon Eye's Plan, then he still needs his Sharingan eye for executing such technique ( and GM's chakra capacity ) and he needs the Rinnegan eye for controlling Gedou Mazo.
[ I thought that Madara was going to use those 100 sharingan eyes to boost his T- Yomi that he wants to execute on the surface of the moon, but maybe I was right in the beginning when I said that, he only has those eyes for observing / learning all the doujutu's of the Sharingan. Time will tell.. ]
THE WAR FINALLY BEGINS! Just wait for Madara Uchiha, just like I said..
AND YES; Killer Bee is a goner, finito! KILLER BEE will sacrifice himself, so that Naruto can escape and of course; for the safety and future of the shinobi world. KB's death is going to be a main factor in Naruto's mental growth and understanding what Nagato meant with his last dying words.
Naruto and KB are both Jinchirikuu's and KB was for sure a helpfull friend during his training lessons.