According to this Engadget piece, Hulu's been specifically blocked on PS3 browsers.
Why? No one knows, but the error message PS3 users now get when trying to access the site doesn't make it sound like a fault: "Unfortunately, this video is not available on your platform. We apologize for any inconvenience."
Hulu's a big-in-America internet TV thing. Europeans can't watch, which sucks, because it's actually really good.
At least American PS3 users are now in the same boat. See how you like it, eh?