Wiki does a lot in facilitating our activity, but to suggest that Britannica would have had an increased lifetime merely by adopting Wiki technology is somewhat laughable.
I was making the assumption (an assumption which I maintain isn't invalid) that having put the Wiki infrastructure in place, and having done a little advertising, the project would have been successful. I don't think Wikipedia was successful because it grew from the FLOSS community. It was successful because anyone could edit it (you could argue that this was entirely because Wikipeida grew out of the FLOSS community). Britannica could have been just as successful if they had allowed anyone to edit.
Because of the poor resource availability to cost ratio our project is sorely lacking alternative solutions on the development side. This results in an inability to produce a 'survival of the fittest' environment for software features. I am concerned that this is a significant risk.
We do, in fact, have quite a powerful development environment. The "open-sourceness"of our software allows for interesting twists and turns in MediaWiki. Others can develop MediaWiki in a ways that we don't have time and resources for. As an example of this, just take a look at the development of Semantic MediaWiki on Sourceforge. This development takes nothing from Wikimedia resources but potentially benefits us on a grand scale. This is facilitated by our commitment to free software - the ability of others to reuse our work and create better things with it
I think we *do* have a "survival of the fittest" development method. Apart from the aforementioned "open-sourceness" of our software, members of the community (who aren't developers) spend their own time developing certain features and additions in the form of bots and tools on toolserver. These features are then put through rigorous practical tests (bots function on Wikipedia, proving their worth and exposing their mistakes). If one of these features proves to be wonderfully useful, it is assimilated into MediaWiki proper.