The 360 and wii have been hacked for a while but the ps3 is standing up the test of time. During that time sony is paying dev's to find holes and patch them.
So any holes open that presented a problem in the lower firmwares are being slowly depleted and since everyone keeps moving on to the more secure firmwares it'll be a lot harder to get anything not to mention anything useful.
A modchip would be the only plausible idea but mostly everything is encrypted at the hardware level due to the hypervisor so i fail to see how it would allow homebrew. Iso's could be the only plausible thing w/ a modchip if it was done more from the bluray drive side kinda like the 360 drives firmware flash.
No one is planning to make a ps3 modechip except infectus which, i heard wasn't fake and was working, but nothing came of it yet.
Im saying its pretty safe to say the ps3 wont be hacked. New firmwares are getting way more secure and no one is working w/ the old firmwares.
Don't get me started on TeamPS3 hax, they are a joke.
Ps3News had some pretty talented dev's on their side but i dont see any dev talk around their anymore.
I heard we have RSX access in linux and the only thing that is preventing us from using it is us lacking a driver but i don't have that confirmed yet. Even if that was true all of you have no idea how hard it would be to create a driver with the limited ammount of info we have. If we somehow got to the point where we could take advantage of the RSX it'd be great but the remaining amount of memory would still present a big problem.