I like it too—I'm running a small test instance and I'm active over on Meta, and I signed up over here mainly to watch the deployment and see how the community shakes out.
In considering whether or not to adopt Discourse for my own personal site, I find that there are two main questions I ask myself whenever an issue comes up:
1) Is this a problem that's due to a bug, and if so, is it something I can live with?
2) Is this a problem that's due to Discourse actually doing something wrong, or is the problem based on my own assumptions and experience—and if so, does it really apply?
Discourse does a lot of things differently than a traditional forum—not necessarily better, but different. Some of the things Discourse does, like out-of-the-box community flagging of spam & abuse, make up for "missing" features (like, for example, moderators being unable to modify some of the security settings that I'd prefer they be able to modify).
Other things are simply bugs that I'm confident will get addressed—I don't always get taken to my last unread post when I re-enter a topic, and sometimes scrolling too quickly through a thread won't correctly mark all the messages in the thread as read. With the rapid pace of development, though, bugs are both inevitable and inevitably transitory.
Discourse's biggest weakness is also its biggest strength—it's a Ruby-based forum that requries a postgresql + redis backend, and if you're a sysadmin whose used to deploying MySQL + PHP applications, there's a considerable learning curve. I've blogged about my own Discourse installation and the particular ways I overcame the hurdles (using Nginx + Passenger to serve the forum, fronted by Varnish for static stuff), but you definitely will not be able to simply clone the git repo down, add a virtual host, and be serving stuff like you might with a PHP app.
But I like it. I'll stick with it and follow the new big sites as they pop up. It's fascinating to see something new and neat, and it's been fun to play with it and get it set up.