Is Mojolicious' morbo (development web server) good enough for production? Also, is morbo good enough to handle many http requests?
Or, must I use Apache's mod_perl for production instead of morbo?
morbo is the development server which comes with Mojolicious, its key feature is that it reloads the app when source files change. The production server is hypnotoad and that is recommended (even for high-ish loads) for *nix servers. If you aren't using *nix, then the basic daemon should be used, which is the underlying server that runs both morbo and hypnotoad. Read more here: http://mojolicio.us/perldoc/Mojolicious/Guides/Cookbook#DEPLOYMENT
You may deploy behind a Nginx or Apache reverse proxy if you would like, proxying to hypnotoad or the daemon.
Mojolicious apps can be deployed using PSGI servers like Starman or under mod_perl or even CGI environments, but they will not be able to take advantage of several of the real-time features that Mojolicious is especially useful for, like websockets.
TL;DR, use hypnotoad or daemon for your production server.