I've just been playing with the latest release (1.222). One of the nicest new features is the Plugin Manager. It looks and feels very much like a web version of the NetBeans plugin manager (maybe this isn't really suprising ;-) ). If you aren't familiar with the Netbeans plugin manager, you get four tabs:

• An Updates tab, where you can see which of your installed plugins are out of date, and upgrade them;
• An Available tab, where you can browse the plugins available on the Hudson web site, and install them if you want. If you choose to install them, it will download and install them for you - this is so much easier than doing it by hand!
• An Installed tab, where you can see what plugins are currently installed on your server;
• And an Advanced tab, where you can configure your proxy if necessary, or upload a plugin by hand.

Actually, the Hudson project is a good example of the application of agile delivery principles. A new stable version is released at least once a week. Even so, in my experience, bugs are rare and upgrades have always gone without a hitch. Indeed, with such a frantic release schedule, the stability of Hudson is truely impressive. You're the man, Kohsuke!