(Timwi timwi@gmx.net):
Unthreaded: in a clear field, Chad, what *would* you have implemented MediaWiki in? And why?
I can't speak for other people, but I would do the parser in C (using lex/yacc) and the rest in Perl.
For the parser, I'm sure the "why" is self-evident. For the rest, the answer to "why" unfortunately includes "I don't know any Python or Ruby". All I know is that PHP is unsuitable for anything larger than a quick hack.
Just for the record, I probably would have done the whole thing in Java except that PHP had two advantages I couldn't ignore: one, it let me get the whole thing up and running in 2-3 weeks at a time when the existing wiki was in serious meltdown and had to be fixed quickly; second, it allowed me to replace some of the existing code incrementally for easier testing.