Wall of text alert!!! ............Just joking
This is for those who are interested in knowing this, for some this is difficult to understand how the sannin got "beat" by 11 year old Itachi, and for some it's obvious defeat. This will hopefully give you a bit insight on that matter.
In this penal Orochimaru decided to challange Uchiha Itachi.
-"11 year old Itachi defeated Orochimaru in one penal" Or "Orochimaru is weak to Genjutsu"...
This is perhaps the most popular statement ever used on forums when discussing Orochimaru's strength or failures..
Well, aside from the fact that Itachi is a prodigy, and the best Genjutsu-user we've seen in the Manga, I'll point out two major problems with this picture:
Firstly, the top-left panel - Orochimaru is bringing his hands together to "Kai" out of the Genjutsu. Why am I so sure he would escape it, rather than just fail like Naruto did? Because of what happened next - Itachi cut off his hand. Itachi isn't a showy, taunting person. He's cold and efficient - why would he cut off Orochimaru's hand, unless Orochimaru was going to escape?
What does this show? It shows that Orochimaru can escape Sharingan Genjutsu. Take in mind the distance as well, shown more clearly on the middle panel of this page. There's a bit over a meter there, no wonder Itachi closed the distance so quickly and cut off Orochimaru's hand!
Now, if there was more distance, then wouldn't Orochimaru escape and be able to counter-attack Itachi? Or, just regenerate the hand, removing what was once a crippling injury to him?
The hand was important as Ive pointed out in this thread; The Void
It's obvious isn't it? Mission failed in gaining Itachi's body, that doesn't say Orochimaru would've lost or got defeated. For many this is common sense..
But for some this is totally unarguable and is fact that because Oro fled at that moment he was "defeated".
I'm not trying to say that Orochimaru is stronger than Itachi - it is fairly conclusive that he is weaker than Itachi, but I don't think Itachi can defeat him as easily as he "has" in the past.
If you disagree, then so be it.. Just be glad he got defeated with Susano'o later in the manga. To be honest, who wouldn't be defeated by that swords...?
So when people say... "HEHE Oro got defeated whot you talking about"..
For a man who killed two Kage and one of them is no one less than the Sandaime Hokage, also know as God of shinob, later on laughed down KN4, and has made other notable people shit their pants, I wouldn't use that against him... >_>