It is also possible to browse through your files using the dashboard, but any sane person (like me, although whether or not I am actually "sane" is up for debate) would just use the good old Nautilus file manager.

Speaking of the file manager, here it is. Surprisingly they haven't managed to screw it up too much, but this "oversight" will likely be "corrected" in Ubuntu 13.04.

You know, with all this whole commotion about saving screen space, why did they just not set the default to hide the tool bar and make it look more like a Mac? That saves space, and has been an option for several years now. I think it actually looks right at home with Unity.

Now this one has me puzzled.

With 11.04 Canonical introduced this new scroll bar. 12.04 has a few visual improvements.
The problem is, this new scroll bar is only present in GTK+ apps that don't use a custom scroll bar. And as such, LibreOffice, Firefox, and even the desktop itself still use the old scroll bars!

At first it isn't visually obvious what to do. Once you move the mouse close enough, a bar that is proportionally the size of the space to scroll appears. However, the actual slider only appears once you have moved within a certain line of pixels on the bar. Inconsistently it may appear on either side of the bar.
Apparently it was designed to save screen space and reduce window clutter. In reality it only serves to make an even bigger mess.

The new Workspace switcher looks like a less dazzling ripoff of Mac OS X's Exposé feature.