Bantam have unveiled the cover art for their new, tie-in edition of A Game of Thrones, due for release on 22 March ahead of the TV show's debut on 17 April (the promo material says 24 April, but this has since changed).
The cover art depicts Emilia Clarke as Daenerys Targaryen, a photograph originally released as the second piece of promo material for the series many months ago.
My understanding is that this new edition will complement existing editions of the book, not replace them (although new printings of the books will apparently be amended to note the HBO series' existence). I assume that this is the cover art Voyager will be going with in the UK as well. The Voyager edition is not just new cover art, but will feature a whole new, 'cleaner' typeface and will be a larger, B-size mass market paperback. Whether the American edition gets the new typeface as well is unclear at the moment, but the US edition will be available in both tradeback and mass-market paperback.
The version on the PDF has a FOR SOLICITATION ONLY warning on it, so this may not be the final cover. In addition, the PDF has a second page indicating that the American editions of the series are going to be rejacketed with the UK cover art, with the exception of A Game of Thrones which has been given the UK cover art for A Dance with Dragons. Since the UK GoT has a dragon's skull on the cover, Bantam may have decided it makes more sense to have that as the new cover for A Dance with Dragons (the third cover design that unreleased book has had, which may be some kind of record).
At the moment it is unclear if these new editions are 100% replacing the existing American editions, but going by the title across the top of the PDF, I'm guessing this will be the case.
On 18 January HBO confirmed that the above art is a placeholder, not the final version. Whether that means the image will stay but the logo will change, vice versa or both, remains unknown.