You might consider this a theorist's question, of no consequence to practising poets, but it raises issues which divide poets. What's at stake is whether poetry should gravitate towards that which makes language unique (poetry being intimately involved with the language it's written in), or whether poetry should strive to escape language ("in its works of literature, a language is pointing towards its own change and development, its own becoming" - Maurice Blanchot). Is poetry beautiful or sublime?
Poetry has been used for many purposes, and competes with other genres, each having its strengths. A musical major-to-minor key change can do what words might take pages to achieve. A few images from 9/11 have an impact that no poem can match (and besides, the readers will already have seen the images). We no longer use verse as Dante or Erasmus Darwin did to expound facts because illustrated prose has taken over. In an increasingly visual age, when sound and moving images are becoming as easy to transmit as the written word, language faces even greater challenges than hitherto. Nowadays, poetry goes down well at funerals but that's about it. Poetry has to cede territory, but on whose terms?
Some poetry has retreated to the citadel, to what poetry alone can do. It draws attention to its medium - the appearance or the sound of the words - or emphasises the difference between words and the world - how a small difference in a word can have a big difference in meaning. The engagement with language is part of the poetic effect, or even the main part. In Rialto 71 Nathan Hamilton writes: "it's my feeling that, unless the primary subject of a poem remains language (directly or indirectly) ... it is likely to appear naive or drift towards unexamined cliché" In so doing it risks gives up the ground where poetry can compete on equal terms with other genres.
There's also poetry that tries to make language transparent - Holub's perhaps, or some of Hughes' Birthday Letters. Sometimes the transparency is so that a voice or events can show through clearly. Sometimes (as in Pauline Stainer perhaps) the hope is that something other than the visible shows through. The poetry tries to leap the frontier, strives to express the inexpressible. Like prayers, spells and mantras, they propel readers beyond words.
Richard Jackson in "The Cortland Review" (Winter 2006) described these tendencies more generally. As Earl Wasserman writes in "The Subtler Language", what I have called an idea-driven poem "directs us as modestly as possible to something outside itself," while language-driven poetry is real poetry "in which reference values are assimilated into the constitutive act of language; its primary purpose is to trap us in itself as an independent reality."
Ostensibly these 2 options betray radically different degrees of trust in language, but there's some common ground. The roots of language are unclear, but ritual has involved the use of words from the earliest times. And however language emerged, it evolved from grunts, roars and hisses. So both these approaches could be said to point back into language's past. The difference is that ritual-based poetry not only tries to transcend language but also the material world.
When poets discuss future trends, their own future is never far from their thoughts. Many poets don't have a range of styles in their arsenal. In particular, wordplay poets and mystics tend not to interchange styles. Fortunately there's a third way of interpreting the situation - viewing the mystics as attempting to expand the resources of language. Arguably Wordsworth did so, creating a readership for his brand of poetry. By expanding the realms of poetry the Romantics also expanded the scope of language. Richard Jackson goes on to say the experience of poetry is the very process of poetry, the struggle of language to discover what is buried within itself rather than to simply report what happened to the poet or what he or she thought or felt. Poetry is a language of discovery and transformation, not simply of "witness." One of poetry's abiding preoccupations is where to draw the line between the word and world.
As an answer to the title's question this may look like moving the goalposts, but in this case readers are both the referee and the crowd, and after all, poetry's only a game.