-Unfortunately responsible for maintaining a Drupal install at work...
Huh? How does "big" make them deserve a custom solution? Huge behemoths like nowPublic.com and spreadfirefox.com run Drupal. Heck, economist.com is >>> techcrunch, and they're dropping their custom solution and shifting to Drupal. IMO, "big" is the least of their concerns if they want to switch to Drupal. TC is perfect example of a website wanting content management. Content is what they deal with.
But, I will say Drupal is not the answer to all problems. For example: if your application deals primarily with data that can't be classified broadly into "content". Like last.fm or chesspark.com or etherpad.com... you get me.
Wrong.
http://siteanalytics.compete.com/techcrunch.com+economist.co...
Page views alone aren't that big a deal in a content website like TC/Econ - you can do plenty of caching, buy more servers etc. Serving the needs of all the various people involved in an Economist-type publication is where the challenge is.