I for one coming from Microsoft based tools, could not figure out how to draw a straight line in GIMP without some googling. I bet it would have been easier in Photoshop. Even now, it is so unintuitive to make small edits for novice users in GIMP.

In the next LTS release of Ubuntu, you will get Unity and not GNOME3 by default. Unless of course you remove Unity and go with GNOME3.

There's a GNOME Remix that we must account for. It's what I have running on a few VMs at work and at home.

The GNOME Remix is hobbled by Canonicals decision to stick with older releases of GNOME and GTK. Ubuntu 14.04 will likely ship with GNOME 3.8 instead of 3.12. For various technical reasons they can't just put the newer version in a PPA.

Why pixels per inch? Why not pixels per centimeter? Isn't metric system the standard? :)

Metric is rational and a standard ... except that a good chunk of our global computer industry is dominated by American corporations, and they still run on the width of the King's Finger :)