Hi,
I've been following with great interest the endeavour to relicense Wikipedia for some time, though this is my first meaningful contribution to it. Attribution is an important and sensitive issue but I think the discussions so far are missing a great opportunity to promote Wikipedia itself while further simplifying (and thus fostering) re-use. Focus so far has been on arduous processes for identifying authors and linking to revision histories which runs the risk of continuing to stifle adoption of content even after re-licensing.
It appears that it would be adequate (as a minimum acceptable standard) to specify the CC-BY-SA license and refer to the Wikipedia article - certainly the license section 4(c) allows for significant flexibility in this regard. The attribution itself would then be something like "Wikipedia 'Widgets' article" which is enough in itself for a user to be able to find the article and associated revision history (concise attributions are critical especially for print work, on t-shirts, etc.).
My primary concern is that it can be essentially impossible to reliably identify key contributers, and that doing so in an environment of stigmergic collaboration can be very misleading as to the value of each contribution (even the most minor of edits play a critical role in the building of trust). It is also a potential source of significant contention, both internally between editors and externally with editors individually seeking attribution from content consumers.
Take for example the cloud computinghttp://en.wikipedia.org/wiki/Cloud_computingarticle which I [re]wrote last year, the vast majority of which is to this day still my work. In this case it is clear from the statisticshttp://vs.aka-online.de/cgi-bin/wppagehiststat.pl?lang=en.wikipedia&page=cloud%20computingthat I am the primary/original author but had I have confined my updates to a single edit there would be no way to reliably identify me, short of tracking the owner of each and every character (and even this is far from perfect). In any case my contribution was intended to further the objects of Wikipedia and if I need to derive recognition for my work then I will reference it directly myself.
Please consider adopting as low a minimum acceptable standard for attributions as possible so as to derive the full benefit from this exciting transition by lowering the barriers to participation.
Kind regards,
Sam