What are your thoughts on placeholder states?

This is one of the title cards that I've used in our recent post on heroes of UX Design

I've been working in the background on some UI designs for an upcoming project for the Compass of Design and our community there.

One of the things that it requires is a lot of data relying on multiple requests which could take some time to load new items in. And instead of having a spinner, I thought it could be cool to progressively load content into the placeholder states of the ui element.

What has been your experience with placeholders?