However, since then hidden features were speculated, and today Naughty Dog's Sam Thompson has stated the following in a Comic-Con 2009 interview (video below), to quote:
"Naughty Dog is constantly working to improve every aspect of the gameplay; be it animation, lighting, sound, texture fidelity."
"You know if you look at the game itself with the 2.80 engine update, you know we're adding more memory, so we get a lot more utilization of the SPUs so we increase our optimization of the Cell processor as well.
So we've got from the engineering side all the way up to texture fidelity, artists adding in even more... I mean there's really not a singular aspect that's not been improved in the game," Thompson added.
A reduced OS memory footprint is a common inclusion with PS3 updates and it's good to know that it's making such a positive impact with developers and their games.
For reference, the PS3's memory footprint was reduced to 74mb at firmware 1.80.