First of all, it's honestly really sad that half the people on the base arn't happy with Kishimoto, Obito was the best decision he could make, as OBVIOUS as it was, the build up and emotion put into all of this is so amazing, that it kept me on edge for a year. What people are failing to understand is, this is a manga, an anime, an alternate universe where imaginary characters don't give two shits if your disappointed or not, because they don't know you exist.
What i'm saying is, your opinions arn't going to effect this manga, because the story goes with how emotional the characters will feel, how much effect it will on the universe of that anime itself. If your really angry with Obito being Tobi, then i'm sad that you don't see the true reason behind it. The true need that Obito MUST be Tobi.
Kishimoto doesn't do this for you, Kishimoto does it for himself, and the amazing story he has created. The build up was amazing, I would be happy with any decision Kishimoto made, whether it's ramen guy or Izuna, impact and plot is what defines an anime. The impact being towards the anime itself, not a bunch of twelve year olds who scream 'ERMEHGERD OBVIOUS' 'WTF STUPID REASON'
Now that i'm done with that..
Why do people doubt Obito becoming like this because of the death of Rin?
Are you all really so blind that you actually doubt the power of emotion and strife in the world, that it would ( not change the person ) but put them on a different path, a path which sets them towards there goal in a much different way. Rin's death was a MAJOR reason for Obito to set himself out on this path.
He sacrificed himself for Kakashi, gave him a light to see the future, to protect the love of his life, and his only, last wish to the world and Kakashi, was for him to protect Rin.
Somehow Obito survived, which is defiantly because of Madara. Madara being evil, could of easily fueled Obito's emotion, turned him into a striver of peace for his own goals. And when Rin died, Obito's mind was set. He hated the world, he hated the fake "Peace" that everyone fought for, and Madara offered him a way of changing that.
Obito could create a world, where no excuses would be made. Where no strife occured, where the world lived in harmony. I'm not saying his right, fake peace is as no good as no peace. But of course, Obito needed a reason to become the main villain of the manga.
I honestly hope most of you understand, there's going to be mainstream morons, who are completely against the idea of Tobi being Obito ( Who would scream at any decision Kishi makes that isn't their own ), who are now screaming because no matter how many useless theories they made, they realise it was always Kishimoto's decision. I'm with Kishi with whatever he does. Because as far as i'm concerned.
Tobi being Obito is the greatest thing that's ever happened to this manga.