Question about 7D firmware upgrade 1.2.1

Canon’s web site says that one of the things changed in 1.2.1 is:

"2. Optimizes program shift when the ISO setting of the camera is set to AUTO."

I emailed Canon Support about this and asked if they could explain it in more detail.

(i.e.: How are Shutter/Aperture/ and ISO changed with respect to each other in Tv/Av/and Program modes.)

The response they emailed back was:

-------------------------------------------------------------------
Dear Canon customer:

We appreciate your continued correspondence regarding your EOS 7D.

There is not specific technical data regarding how the shift was
optimized. The camera will better adjust the ISO for the lighting.

We hope this helps. Please write to us again if you have any questions.
-------------------------------------------------------------------

I must admit I am disappointed in the quality of this answer provided by Canon.

When in ISO Auto, does anyone know how Canon balances the ISO, Shutter, and Aperture values against each other depending upon the camera mode (Tv/Av/Program) in version 1.2.1 ?

Thanks.