I'd heard about this...there are a lot of questions.
The fact is, no matter who writes it or how well, it won't be Douglas Adams -- so, in my heart, it won't be real Hitchhiker's. It'll be paid, published fanfic.
An author in this position has two pressures: one, to write the story he's told to write, and two, to make that story and writing his own. Unless the author is utterly without self-respect or at least a sense of identity -- I'm looking at you, Chris Tolkein -- that second pressure can never go away. An author can change voice but it's still his heart, his ideas, or else we'd just finally give up and build Adams-Bot 3000 to write us infinite automatic reams of what it's like to be English in spaaaaaaaace.
Overall I think it does authors a disservice to try to create "official" continuations like this. Sure, give unfinished notes to scholars. And I agree that some of literature's greatest works are continuations -- but those continuations were the work of the subsequent author, borrowing a character, but free for the inspired following author to do whatever they like. They were unconstrained, writing only what they loved and discarding the rest. Shakespeare can borrow from wherever he likes and write Hamlet; Tom Stoppard can write Rosencrantz & Guildenstern are Dead; but nobody should write Hamlet II: Horatio's Revenge.
And hell, DNA didn't hold himself too closely to his own continuity, so why should anyone else?
And the other thing, the thing about series is -- stories end, even if they're written by Roger Zelazny. They're supposed to. It's part of their humanity; people end. Sometimes abruptly. Sometimes unexpectedly. Often imperfectly, without complete resolution.
It's natural to want to round them off and to think about what might have happened.
But all you can do is think about it.
And that's life.
Er Adams wrote too many Hitchhikers books so I hardly see having someone else write one as a bright idea.
Mmm Republican Party Reptiles (I have the faint suspicion that I have read that and forgotten that I read it). You could adapt that to "The fans hate the book. Why has it sold so well then ? The fans bought it. But they hate it !! Well its a Hitchhikers book isn't it". Rather like a thread where someone likes the film Rear window and had seen some trailer for another rip off variant and wants to see it because he liked Rear Window. People are dumb.
The fans bought it. But they hate it !!
Purely as a business model, it can work well.
Look at George Lucas.
*seizure out of disgust*
Horrible idea, though I doubt he'll manage to make it quite as dreadful as, say, KW Jeter's "Bladerunner" fanfic.
Fortunate enough not to have read those. (Remember "Warped", one of his two DS9 novels, being really really awful, though)
The only even vaguely decent thing I've ever written by him was a DC 'Books of Magic' spin-off about Mr. E. It was still not great though.
I've nothing against Eoin Colfer (though i'm not a great fan of his work) and it's great that he seems to have a lot of respect for Adams' work, but...
Why bother? I can't think why anyone would want to do this, except for the money. And it seems rather odd that Adams' widow is okay with it.
Well, Adams eventually came to be unhappy with how Mostly Harmless ended, and wanted to end up with the characters less, well, dead.
Hi. Noticed you have some blank maps of the English counties in Wikipedia. You wouldn't happen to have one of the traditional counties, would you? There's one at http://en.wikipedia.org/wiki/Image:England_traditional_counties.png but it's really too small for my purposes (an academic publication). Wouldn't mind if Wales was shown too, but even just England would help enormously. You can contact me via http://www.helsinki.fi/varieng/people/varieng_saily.html