I agree that poetry isn't "superior" to other media, but I do propose that it is a hybrid medium as it incorporates a visual aspect (when read first-hand) but is by its nature a musical medium.
Like music, it exists only as it is occurring through time, while a reader is engaging with it. Each poem is itself a separate Event--an occurrence, a script for a moment to be performed *that exists only to be performed and is nothing if it is not* (though, in this context, performance could be as simple of an engagement as silently reading it "out loud in your head"). It is, after all, this interaction that makes art art--but unlike more "physical" forms of art whose disclosure is constant (once revealed a statue or a painting permanently Is [not to introduce a semantic argument]), poetry's disclosure (or its music) is definite and inconstant.
Unlike music, however, it has a reflective depth and self-questioning that only language can provide. (crossing into the synesthesia of poetry and music combined being more complex than the description I'm attempting now, while prose generally disregards musicality in favor of meaning) The implications and connotations of all words--not to mention the visual images subconsciously attached to them--allow layers of depth and meaning to be constructed and to build themselves. The best poetry transcends even the meaning that the author intends; although simplicity has its place and its beauty, gems with thousands of facets sparkle more brilliantly, and sculptors must choose the size of the stone.
I highly recommend Martin Heidegger's "Poetry, Language, Thought" to anyone interested in this issue in a philosophical (aesthetic/metaphysical) context...although it is admittedly quite plodding, its classification of the poem as a work of art is thorough enough to be beyond convincing--and accurate, to boot.
I hope this description doesn't seem too didactic, though I'm sure it does.
Excellent thread Cherub
