Stable as a refrigerator.
A full office pack, image editor (gimp), and a lot of useful programs.
Desktop effect (compiz fusion).
A bright OS (the general color of the default theme).
A top bar like in OS X.
The deskbar applet from Ubuntu.
Inbuilt weather applet in the taskbar.
A light weight music player, that can find (and play) music, and nothing else.
Plz. make standby and hibernate work on most laptops
Make it easy to dual-boot with any other operating system.
Google applets (calendar, gmail, docs) are build in to the system. (Sync offline calendar with google calendar)
Preload technology (Like superfetch in Vista, and Preload in Linux.)
I wanna install it on a USB pen
A menu system like gnome, so you easily can find a program by category.
The KDE4 desktop is just cool, if you could make something like that, it would be awesome.