I've only recently joined this list, so I can't speak to any community efforts that may be underway, but I'm happy to share our status with you.
We're currently running Banner 7 (with an upgrade to 8 coming this fall). We have Banner/Portal integration for courses, grades, holds and advisor information. Our production portal is Oracle Portal 10.1.2, so unfortunately our portlets are somewhat proprietary. Our courses/grades portlet is originally from the University of Montana (I believe our initial connection with them was through CEAI/CDC). As I understand it, much of the data layer of the portlet was re-written to suit our Banner environment.
Moving forward, we have a uPortal beta running that we hope to move to next semester. I've written a new portlet front-end that runs on the client side and accesses the Banner data through a JSON web service (which is wrapping code that was simply ripped out of the original portlet - it's not very pretty).
I had already planned to rewrite our Banner integration, so I'd be very interested in collaborating. Also, if anyone listening will be at the Gettysburg conference next week, I'd love to talk to them.