Ubuntu will be following the normal market trend of releasing custom-built images for OEM hardware, working with the manufacturers to get the boot time as low as possible. Shuttleworth is claiming that Unity will have a 7 second boot time using SSD.
What does Unity look like on my netbook? Take a look.
Compare this to Hyperspace:
And to Express Gate / Splashtop
Unity give more of a functional look to the genre, departing from the other's spartanism, which I think will give customers a feel of more control and greater ability.
As far as I can tell, it is not possible to modify the left launcher directly. I tried to add Chrome (my preferred browser), but couldn.t do it until I already had Chrome launched and the icon appeared in the launcher, allowing me to right-click and pin the application to the panel. You can use the top folder icon to gain access to installed applications not on the launcher panel. If that icon choice seems unintuitive to you, know that you are not alone in thinking that.
The interface is clean and easy to use. Within two minutes, I had discovered everything I needed to know to get to work. The panel iicons have an arrow on the left side when they are running, and the active application is identified by an arrow on the right. If you have more than one window of a given application open, right clicking will give you a scaled view of all the application's windows.
My one complaint about the interface is that it is quite easy to get notification windows which bleed off the bottom of the screen., but that shouldn't be a problem for most people using the interface as designed. Unity is already 90% there, and you can expect that Maverick (to be released 10/10/10 -- is he a numerologist?) will operate amazingly well with this interface.