It's two dimensional - the program counter can move not just right, but left, up and down as well. This makes loops neat - they are natural, and don't require that the program counter should jump.
I think that this could be important. It's just a suspicion, but the increased naturalness could help evolve programs in the field of artificial life. Like Tierra.
Being a two dimensional programming lanuage, it is ideal for sitting inside a spreadsheet.
You can download my Excel spreadsheet implementation of Orthogonal. It's easy to use, and lets you watch the program as it runs.
You can find out more about Orthogonal from its home page. Or you might like to look at ZBefunge, my implementation of a slightly earlier 2D programming language.