I'm starting to be settled on a position on attribution:
An Approved Open Source license may name an Original Author, and may require that a majority of users be able to name the Original Author. The license may not dictate the means through which that goal is accomplished. The license may not impose this requirement if less than one-third of the software is present in a derived work.
It's testable, and scales because at most three Original Authors need to be acknowledged. It is also congruent with OSD#10. It also rules against the SugarCRM license which is currently annoying so many open source developers.
I could be talked out of this if you have a sufficiently good argument. Send me email.