Luke Pond has just finished porting the ACS 4.x portals module. We should definitely take a better look at it. I was under the assumption that it was a fairly straightforward mapping of the ACS 3.4 portal package to the ACS 4 framework. The ACS 3.4 portal package (at least the one in ACES, which I've been working with recently) gives more flexibility but only at the portal, not portlet, level.
If Ian already implemented some similar ideas and if they're in the public repository, hooray! We already have it. If it's just in an aD CVS tree somewhere, we don't.
Do you have an e-mail address for Ian? He should become one of us!