So I joined Jot about 6 months ago, and shortly after I joined I found myself at lunch with Graham (among others). As I started to ask questions about how the system worked, it seemed like every sentence that I'd start as a question, he'd finish with "yes, and it also...". It is, in short, amazing. It's everything I thought a web app platform should be. Sure, it might not be polished (yet), and it might not be what you think of as a "web app platform" in the classical sense, but don't let that stop you from reading:
If you read it and get it, I mean REALLY get it, it will completely transform the way you think about building web applications. And then you'll be as hooked on Jot as I am.
And you'll probably even forget that it's also a wiki.