You can log into the OS with any Google account, such as one for Gmail.
The first difference between Chrome the OS and Chrome the browser is that
you can pin smaller tab (those at the upper left) for always-available web
app access. Sort of like Windows 7's pinned app taskbar buttons.
The very first tab, sporting the Chrome icon, is another way to access your
frequently used apps (aka sites). It also sports a search bar, though the address
bar in Chrome is also a search bar, so I'm not sure why that's there.
This is one of Chrome OS's true innovations: For things like IM and Notifications,
these small windows remain on top of the main browsing window.
Multiple desktops are switchable using this overview mode, as shown here.
Note the panels remain on top even during this operation.
Standard USB storage devices will be recognized by Chrome OS when you plug
them in, and their contents will appear in a panel.
If you don't have as many primary apps/sites as shown in the second slide above,
here's another look for the Chrome tab. Keep in mind that the Chrome OS user interface is
a fluid work in progress, so we'll probably see several variations before it's released.
You can drag a panel to the side of the screen to create a sidebar.
