Python + JavaScript + Flash. The server-side choice between Python and Ruby is completely arbitrary; I suspect either one could do the job equally well. I was swayed by the somewhat greater availability of libraries for Python, plus I thought it'd be easier to get Python programmers if we got big enough to hire, plus it's somewhat more likely that an acquirer will use Python than Ruby. PHP or Perl could also have don…
Nostra... what's the front/back ratio? I remember reading Ryan from Wufoo's "Web App Autopsy" ~ ( http://particletree.com/features/web-app-autopsy/ ) was quoting 60% front-end to 40% back-end code ratios.