I didn't even notice that Amazon bought Cloud 9.

Coming from Sublime -> Atom -> VSCode it looks a bit like the older versions of the editors I used in the past.

I come from Vim -> Atom -> VSCode -> Cloud9, and have become a deep C9 loyalist. I love the window management, terminal integration, speed, and ease of configurability... No other editor I've used even comes close. And that's to say nothing of its being cloud-based

Hehe.

Does this cloud based part not lead to problems? Like what platforms is this thing running on "in the cloud"?

It's never lead to problems for me. However, some of my coworkers decided not to use c9 due to latency (which has never bothered me for some reason.)

I use the ssh-workspace feature and do my work in an EC2 instance. I've also been playing around with running a local c9 build (https://github.com/c9/core). Not sure that their license would make this viable for commercial work, but ofc there's no latency / connection requirement if you're running it locally.

Off-topic, you could even run c9 locally in a Chromebook if you were using Crouton -- and without having to install another desktop environment. I do most of my work on a desktop, but if I ever get together a mobile development environment this may be what I do.