It's really a matter of the Xbox 360's warranty which is good for only one year for non-RROD errors. That means that all three times that I've gotten disc is unreadable errors, I've either had to pay 100 dollars for repairs or had to try fixing it myself (neither solution is pleasant). Also I want to point out that a one year warranty is FREAKING RIDICULOUS! Who buys a video game console with the idea that they only are going to be able to play it for a year? I'm on my fourth Xbox 360 now BTW.

On the other hand we have Nintendo. They will fix all your problems even when its obviously your fault. For instance, this is a real conversation a friend of mine had on the Nintendo costumer service hotline a few years back:
Friend: Hey, my Gamecube stopped working.
Nintedo Representative: What happened?
Friend: Well I was playing on it when my little brother ran through and tripped on the wires, knocking the Gamecube down, which caused it to stop working.
Nintedo Representative: Oh that's, too bad... If it broke on its own we would repair it for free.
Friend: Yep...
Nintedo Representative: Are you sure it didn't break on its own?
Friend: Um... Yea?
Nintedo Representative: Think it over a bit more... Because we'll repair it for free if it broke on its own.
Friend: Oh! Right... Yep, definitely broke on its own.
Nintedo Representative: Super, we'll repair it for you for free right away.
Nintendo as you can see treats is customers like people unlike Xbox who treats its customers like yesterday's garbage. But the thing is, Xbox 360 is still creating games that I want to play. There are six upcoming Xbox games that I want to pick up, while the Wii only has two or three (before the E3, I was only looking forward to one Wii game). It was like for a while, Nintendo just stopped caring about us and just became content selling over-priced bathroom scales to our moms. After a year of not caring about the Wii, it seems a little difficult to care about them again. Let's hope that the upcoming Wii games rise to the challenge.
The fate of Xbox 360 has yet to be seen. Although, I'm buying their games right now, I don't have any particular loyalty to them. Next generation I may have to pick up a PS4 because I never want to go through the Xbox 360's customer service nightmare ever again.