AAC Tools used in iTunes AAC, Is it possible to determine which tools are used by the encoder Options

[enry2k]

AAC is made up by a toolkit, so that each encoder implementation can use some or all the available tools. I was wondering which tools are used in the iTunes encoder, which provides very good audio quality. Example:
Temporal noise shaping, perceptual noise substitution, predition.
Is there a piece of software like Mediainfo to find out the tools used by the encoder in an audio track?
What can be tuned up to make an aac encoder sound different from an other encoder?

Best Regards
Enrico

[Dynamic]

I suspect that more than the tools used, the psychoacoustic model's decision making is the major difference between encoders such as iTunes, Nero and FhG.