Before taking a look at the Unity launcher, a small off-topic message: like we announced on Facebook, the whole WebUpd8 team (even though I'm the only one posting lately, we're all there :D ) will be unavailable for 3 days because of THIS. I will however try to catch up during the night. Thanks for understanding & rock on!
We knew how the Unity launcher will look from the mockups Mark Shuttleworth posted 2 months ago, but I bet nobody imagined it will look so gorgeous:
And it's not just the looks, it's also smart because it integrates Zeitgeist.
The Ubuntu logo in the top left corner is not for Expose anymore, and it now triggers the Unity launcher which comes with 2 tabs: one for the applications - which you can see in the screenshot above, and another tab for files grouped by day and by type, using the power of Zeitgeist, as you can see in the screenshot below:
Unfortunately the Unity launcher is not very functional for now. In fact Unity itself it's very buggy: a white screen is displayed on my computer when logging in (although it used to work just fine before) so I have to launch both Unity and Mutter manually. And the Unity launcher needs a lot of work: there's no indicator telling you that you actually clicked a file / application and the search is not functional for now. But hey, it looks great, right?
If you want to try out Unity in Ubuntu 10.04, see the instructions @ Ubuntu Wiki.