Why hasn't the PS3 been hacked?

Where is the PS3 homebrew scene? Considering how active the PSP scene, one would think that Sony's other console would get the same kind of attention from hackers. It's not that people aren't trying -- rather, it appears that Sony has learned from their mistakes with the PSP.

PSP was rather insecure from the start. A primer from "nikkelitous" explains that "the PSP didn't have any security protections in the first version: Thats right! It essentially ran anything that you put on it." In spite of Sony's continued attempts at fixing PSP security through firmware revisions, the damage has already been done. "The PSP now has a very powerful security system, but like the Greeks, we had people inside. Once a system is hacked and understood, very little can be used to continue to protect it."

Not only has Sony made the PS3 much more secure, but its use of Blu-ray makes it significantly more difficult to hack. "It's not using a DVD drive it's using a custom Blu-ray drive, we can't simply copy the disks, and we don't know enough about the firmware on the drive to accomplish a 'debug mode' even if it's on there." Of course, all of these hindrances aren't stopping the hacking community. They're going to keep on trying, and will probably one day succeed. However, it's clear that this time around, Sony isn't going to be taken off-guard.