I can think of the Calligrames of Appolinaire who used the words of a poem to draw a figure condensing the meaning of the poem. Like this war horse, one of his poems of Peace and War. Don't ask me for a translation, the hand writting is notoriously impossible to read.
Please enlighten me, now it could be any picture that has some letters scattered on it. I am guilty to have done some.
Dear Martha, it seems to me that in the art world all concepts and categories move from a very definite meaning - to blurred and most general notions, almost without shores. It's a general trend and I don't like it very much.
I had to look through the catalogue of the Archive of Concrete and Visual Poetry in the USA. It's a magnificent collection, and it has every imaginable and unimaginable visual object, similar to Apolinaire's calligrams and totally unlike them. Here's information about the collection, take a look!
Thank you Ilya. Now I know what is Visual poetry, anything I say it is!