MTV's RealWorldDailies.com was built on the Flux (yes "Flux") platform that's very popular to build on in overseas countries such as Australia. It was fun to use and was certainly a good tool to learn CMS's on.
Although Drupal is the clear CMS of choice for heavy duty web sites, any CMS is fair game. Especially if you need to perform a migration from a lesser performing one to Drupal -- Migrate the data, create new, similar content types, tweak the theme, etc, etc.. I'll work it out for ya.