There is a certain class of high scale enterprise client that always voices strong prefernce for AEM. I think it might be because AEM at one point was ahead of their competitors and so a lot of the existing enterprise level companies use it in production and have experience on it? Or maybe they think everyone at that operating scale is using it, and so it must be the best choice... truth is the development experience is painful and it usually isn't the best tool.

My agency had a contract to make a site for an Amazon event. They specified that we had to use AEM, probably because Amazon uses AEM on some of their other properties, but it was not a good fit for quickly standing up a limited scope event site.

Analyst reports, compelling demos at conferences, ecosystem of professional services partners with a relationship with the software vendor (implied promise of escalation of issues), 24x7x365 SLAs, competitor success stories using the same technology, existing training materials along with distant promise of developing in-house expertise by working along-side system integrators.

Just curious, which OSS CMS would you recommend for that kind of site?

I work with Drupal and WordPress, but would not recommend them for user data or transactional data (although in my case, we bridge Drupal/WordPress with CiviCRM, and that works relatively well).

Wagtail, you get a great CMS on top of a powerful framework (Django). Best part of Wagtail is that it doesn’t get in the way of Django so you can drop it into any Django project with ease.

Another variation on "Nobody ever got fired for buying ${big_corp}"

Would like to know what open source CMS offering has a very mature offering? Wordpress is fine for a blog/news site.

Django wagtail is pretty great.

Liferay?

Examples?