A few days ago, as I'm sure most of you noticed, the Agatha Christie estate announced that crime writer Sophie Hannah has been commissioned to write a new Poirot novel to be published in September 2014. The novel will be set in the late 1920s, between The Mystery of the Blue Train (1928) and Peril at End House (1932), so the character won't be resurrected from the dead, as some reports suggested (that would have been a seriously bad idea). The media coverage was massive (see, for instance, the BBC, The Guardian, The Independent and The New York Times). First reactions were largely negative (see, for instance, these pieces in the Guardian (they seemed to have missed the 'resurrection' point, though) and the Independent, not to mention the comments sections and the Agatha Christie Facebook page (for fan reactions)).
Personally, I'll reserve judgement until I've seen the finished product. However, I do struggle to see what a new novel can add to Christie's position as the Queen of Crime. Still, I understand (to some extent) the reasoning behind it. As the links above suggest, the family and the publisher see this as a way of renewing the interest in Christie and grabbing the attention of a younger audience, much in the same vein as the computer games and comic books they've released in the last couple of years. Keeping Christie relevant and at the centre of crime fiction is both necessary and important. Also, from what I've seen so far, Hannah seems to be a real Christie fan who will hopefully stay true both to the character and the novels (I would be terrified at the pressure to succeed that she will be facing!).
I think Twitter user and Christie researcher JC Bernthal summed it up accurately: 'I'm looking forward to reading Sophie Hannah's new Poirot novel. But the Agatha Christie brand does not equal Agatha Christie'.