Well, I'm sold. I checked out Mongo before, and it was relatively pleasant. But I wonder if Couch is more reliable and mature? I'd love to dive into building a brand new system I have in mind that seems like a good fit for a document database.
I've used it with rails for a short time now, still trying to dig deeper -- I really don't know if it's more reliable or mature than Mongo, but it was also a relatively pleasant experience. Also, I do know that it integrates very nicely with rails, and that you should use couchrest with it if you're on rails (http://github.com/couchrest/couchrest).
Side comment: learning to write map reduce algos instead of just querying was kind of difficult at first (for document databases in general). The article seems to have neglected to mention it -- it had the steepest learning curve in the overall couch-learning process for me.
In my few months with Couch I've found it to live up to its "relax" motto, at least until I hit pagination. What you have to go through will seem grotesque to anyone coming from SQL.
haven't used this but i saw this on SO the other day ... I just started looking at the whole NoSQL paradigm to experiment in the near future and i felt it was helpful to track some tags on StackOverflow to learn about issues people face...
I haven't written any CouchApps (I really don't like JS so much I'd like to write my whole app in it, even though the notion is quite awesome), but I've used CouchDB in a few projects. Most importantly, we've been using it at work, where it's awesome at solving some of our problems. Streaming replication to our off-site backup server was almost trivial setup and makes it easy to switch our entire operation to the using the backup server instead of the local network. Map/reduce queries have made it possible to provide very fast overviews of large amounts of data. And it's just awesome that you can debug your queries by firing off HTTP requests from your browser...
Oh yeah, and Futon is an awesome tool. On some of the sites where I've been too lazy to build CMS tools, I'm just using it to update the site, and it works quite well for that. It also makes it easy to just jump in and fix something up whenever you need to.
Also, the article says that views can just be written in JavaScript. It's true that the default query server is written for JavaScript, but query servers exist for other languages, including but not limited to Java, Erlang and Python.
