The curtain has been lifted on the imminent Grey Knights release with some glorious teaser pictures and background article by Simon Grant; see the full three pages here at the Astronomican section over on GW's website, in the meantime here are some of those awesome miniatures to whet your whistle.
Best 'til last...
I've gotta get me one of those! Check out GW's advanced order page here for even more.
Pictures used copyright Games Workshop Limited 2000-2011