ID-FF1.2 and SAML 2.0

Hi,

I have gone thru the SAML 2.0 specs and I was wondering if there is any
documentation/information of what was not carried forward from ID-FF1.2
For example, ID-FF1.2 there is discussion of common domain cookie which
is not there in SAML 2.0 specs.

I joined this TC recently and so  -- excuse me if this has been addressed before.

Thanks,

/Prasanta