Thanks to gamera_spinning, some more information on Longhorn.

The major features, and my reaction to them:

More system self-tuning, and not just in terms of the placement of tasks on menus based on how often a user selects a given option. Think of all menus becoming more like the Favorites option that would be applied to more than just Web pages;

Oh, yeah, that's just what I want — menus which change on me. I hope this can be disabled, because I know where items are in the menus; when I open up a menu I automatically move the mouse pointer down to the area where the item is located. If I have to hunt for it every time to find out where it's moved to based on frequency of use, I'm going to be severely pissed.

Better multi-monitor support, including support for displaying the Windows Taskbar across multiple systems simultaneously;

This would actually be a nifty feature, if I had the room for two monitors on my desk.

More explicit error messages, especially around copying/moving files and handling documents and digital media, in general;

Windows has been around for how many years now, and they're just now getting around to making the error messages explicit and (presumably) helpful?

Easier application installation;

Because double-clicking setup.exe is just so hard to do! (Personally, I don't want "easier application installation". I always choose custom setup, if it's offered, so I have complete control of what components are installed and where they go.)

More stringent user permissions. In the same way a parent can control a child's account via MSN 8 Parental Controls, system administrators will be able to use the latest Passport and security controls to lock down users' machines;

Observation #1: Microsoft equates end-users with children. Observation #2: Hey, have they fixed Passport yet so that crackers can't get your credit card information? Observation #3: While it was difficult, but still possible, for me to avoid signing up for Passport under XP, I'll bet it'll be required under Longhorn.

More self-healing and automation of daily operations. The ideal: Insulate average users from having to do any routine system maintenance tasks;

Apparently Microsoft considers end-users to be idiot children. I hope this can be turned off as well, so that people who know what they're doing can continue to set such tasks up on a specific schedule.

Better management of plug-ins and ActiveX components, beyond what is done in the system registry.

So are they keeping the system registry? (Worst "innovation" ever. I'd like to see an innovation where a clean system reinstall will preserve the application data from the system registry, so you don't have to reinstall every smegging application.)