One of the striking differences after installation is the Windows 8 Start menu,
This resembles a desktop version of the user interface in Windows Phone 7 and Windows Phone 7.5. An oddity that I found was that the applications do not show up in the taskbar when launched, but can be seen using the Task Manager. I'm not sure if this is something that Microsoft intends to fix before the final release, or if it represents a change in direction away from the traditional Windows look and feel to the newer wold of tablets and gestural interfaces.
Overall, I'm mixed on my first impression of Windows 8. It seems like Microsoft is trying to embrace an emerging model with the world of mobile devices and tablets, but I found that most of the things that were familiar and made Windows easy for an administrator to use are missing (but this is only a developer release, so it may get better with time...)