What do you like best?
Wagtail has been developed with the web manager in mind. It helps simplify the management of complex websites.
Thought has gone into everything from how Wagtail features are labelled to predictive text for image searches. All these little things help to save time. From an interface point of view, I'd liken the design to being something Apple may produce.
I find some of the well established CMS solutions cumbersome, slow and confusing. Bolt-ons and extra modules make the experience far from seamless and bug ridden. The website we had before was built on Concrete 5 and we had many problems. With Wagtail there may have been one ... or even two in a year. But nothing more. This gives confidence in the robustness of the code base.
I also like the fact that new and exciting websites are being built on it., like: http://www.destinationspace.uk/ .
What do you dislike?
With it being a new open source CMS, people can be wary about using it. But there's a strong support community building up. And if you look on GitHub, there's plenty of action around the platform (be warned, only go there if you are a developer!)
For the less technically minded, you can see some of the sites that have been built on it here: http://madewithwagtail.org/
It's built on Django, so there should be plenty of people around who can quickly learn how it works, if needed. A number of digital agencies have embraced the CMS already.
What business problems are you solving with the product? What benefits have you realized?
I launched a website using this CMS one year ago and it has performed above expectations and we've seen site visits more the double to over one million. So it's more than proved itself to be Google friendly and technically robust.
I'm also told that due to the way Wagtail is created it takes around 20% less time to build with than Drupal. So there could be some big revenue savings.