WordPress as CMS for online news publication

We are currently using an open source cold fusion platform (FarCry) to host our news site, insideARM.com. We regularly write stories daily along with analysis and research pieces. We’re considering shifting to WordPress but our developer is suggesting not to. Here’s his argument:

I think we’d need to see some example sites these guys have done with similar scope to iARM. You guys have an absolute TON of content (20k pages listed in Google), and systems like WordPress are just not set up for that kind of volume. That’s the same kind of problem we had with FarCry’s admin interface just not wanting to deal with 12k news articles, and I fear we’d have the same kinds of problems with WordPress.

There are definitely advantages to WordPress, and I use it frequently for small sites, but it doesn’t seem like a good fit for you guys. If we were starting from scratch today, I’d recommend FarCry or Drupal.

Maybe with the publisher consultants on hand WordPress would go well, we’d just want to be 100% certain they’ve done a >20k page site with it. If they haven’t, I think we’d want to have them to a demo version first, loading all our news & content up so we could see how the admin interface would work.

Is this accurate? Or are there publishers out there who produce a significant amount of content that is easily managed in a WordPress CMS?