I’ve been using Quip for the last few days and really liking it. The ability to move between devices1 without friction has allowed me to work on some medium-form pieces at times/places I wouldn’t have without it. I’ve also used it to get feedback on various content drafts, which has worked nicely.
So far it’s a compliment to WordPress for me, but I can see more and more of my medium-form content getting written in Quip first before publishing it in WordPress. I think WordPress is due for a great, simple collaborative writing plugin2 and I’d say that Quip is a pretty good model to follow.
Check it out if you haven’t already, it’s really well executed – especially for a 1.0.