In a recent interview Microsoft's director of product management was asked why there was no browser on the Xbox 360, and if one will ever be made available. Don't bet on it anytime soon.
According to an interview with Inside-Games, translated by Sankaku Complex, Aaron Greenberg said:
We really believe that the web browsing experience on TV is a poor one, and the real magic is to take those web experiences and optimize them for the living room. That's what we did with Netflix. So, sure, you can go on the PS3 and go to Facebook and and try to navigate, but it's an absolute nightmare.
No disrespect, there's things I love about the PS3, but that's not one of them. We want the online experience to be fun and optimized for the living room, and we'll continue to add more applications to get more richness.
Though Greenberg's candor might be a little much, it's hard to disagree. Even with a chatpad I can count on both hands the number of times I've used my PS3 browser.
Then again, I can count on one hand the number of times I've used my 360's Facebook or Twitter functionality.
Microsoft: 'No Web Browser on the 360!" [Sankaku Complex, which has some NSFWish images all over its site. Thanks to Manly_McBeeferton.]