ProcessWire isn't just the best PHP CMS out there right now; I'd argue it's the best thing to happen to the CMS landscape in the last few years.

There are more powerful CMSes out there, to be sure, but the crazy thing is just how completely unprecedented PW's power is for its ease of use. It's easy like WordPress, yet it's scalable to enterprise sites with deep content taxonomies.

And it's elegant. Ironic for something built in PHP, I know, but working with its simple building blocks of templates and fields and its jQuery-like content selectors comes with a feeling of "why didn't someone do this a long time ago?"