Its kinda hard to push a processor to the max. The only thing that really specifies the 'max' of the PS3 processor is its cooling capabilities of its fans/heatsink. They'll push it to its boiling point and then say its 'maxed out'.
For example, a 2.8Ghz 6-core AMD processor can be overclocked to 5Ghz PER CORE using a liquid nitrogen cooler. 'maxing' out a processor is a relative term. Its full capability is based on your ability to keep it from melting itself down, and supplying enough power to it to do the task at hand. Of course you aren't going to get a 233mhz Pentium to overclock to 10 Ghz because it doesn't have the conductive capacities to pull enough amps, and even if you tried, it would still melt regardless of what you were cooling it with.
The PS3 processor won't be maxed for a while. The Phats might be maxed soon enough, but eventually there will be a firmware update with a hidden feature that allows developers to overclock processors, especially in the Slim, to take better advantage of 3D capabilities.. etc.
