Comment from Su

One thing to keep in mind is that this is actually a beta, and not what tends to be called one nowadays, eg., "We don't want to commit to a formal release, and putting 'beta' on it means you can't complain." Those black sections in the interface, for example, are almost certainly missing background images(rummage around in the mt-static dir). Anyone silly enough to use this on a production site is looking for an adventure(where you'll find your modal dialog problem, BTW).Many of the more interesting features, like being able to clone a blog, are being handled by plugins, many of which were already available for MT3. You're glossing something very important here. Features being handled by plugins(or components, which are sort of more powerful, lower-level plugins) is in large part the point of MT4. Even blogging, what is probably considered the core of MT at the moment, will be a component which can be disabled or removed altogether. At this point, minus the enhancements to the templating language—just themselves providing huge improvements to functionality—the beta(and remember it's the first one) is largely a straight upgrade of the existing functions. The really neat stuff will come about from plugins taking advantage of the system improvements, like content customization, new archiving types, built-in system-wide ratings, etc.